MatraSport Forum

If the car hadn't been OK for a couple of weeks after I got it back from the 72,000 mile / 120.000 km service then I would have thought that the starting problem was something to do with what they had done during the service.

Instead of it firing up immediately once the heater plug OK light has come on I now have to crank the engine over 6 or 7 turns before it comes to life and it can be even longer when the engine is already hot.

I've had a couple of doses of injector cleaning fuel additive through it and also changed all 4 heater plugs but it's still no better.

Anyone any other ideas?

I have wondered if it may be the heater plug relay that is malfunctioning but half the wiring loom seems to go into that and without a wiring diagram I wouldn't be sure which terminals are which and I haven't found anything in Lennart's "Vault" specifically relating to the this relay either in the G9T engine bulletin or in the German "electrik" PDF. But then I may have missed due to my lack of German language skills!!

thanks in advance for any input

Martin

Hi Martin

There's probably nothing wrong with your German language skills, as the wiring diagrams aren't included in the "Electrics" manuals. I'm sitting here with the diagram for your car... and I'm think whether it would be of any use to you?

There's a lot of electronics in there and it could be lots of things that are wrong. The engine management computer seems to have more than 70 wires going in and out of it, and there's also several additional heaters too. I think the best would be to run a diagnostic scan on the engine computer, hoping that it "knows" what's wrong already.

I can make a scan of the diagram if you absolutely need it, and then you could work your way through each and every wire to check it. But as we don't have any means of checking the sensors, the chance of succes in identifying the problem is probably quite small.

I'm afraid that wasn't much help... ;)

- Anders

and I assume it is not related to the current UK contaminated fuel-scare ?
Initially I thought it was only petrol, but a number of diesel owners have had breakdowns as well ??

On petrol cars, the oxygen sensor goes awol - not sure what the diesel problem does to the engine, but certainly a lot of people have reported breakdowns. Mainly using fuel from Tesco and Morrisons, but now Shell have been mentioned as well.

But if a sensor is damaged, there should be some fault reporting in the car. hmm.

/Lennart

WHAT is that about? It will take some effort to kill a car by putting something in the fuel, for example the "old trick" putting sugar in the tank (has been reported to kill german cars during the occupation in WWII) can not kill a car. Sand could probably, if you put in a lot, but sugar is just dissolved in the petrol and burnt in the cylinder.

So without knowing, I'd say that it's probably more of a rumour than a fact... but then again, I'm in Denmark. So please share some info. After all, fuel supply is a global business :)

- Anders

This one is very much real:
http://news.bbc.co.uk/1/hi/uk/6410511.stm

A colleague of mine has got his car in the shop :(

Thanks for the link, silicone would be one interesting possibility and the SiO₂ being produced in the cumbustion is just rock so the expression of "a stone dead engine" gets a whole new meaning! :D

If the SiO₂ sticks to the oxygen sensor, then it can also stick to the valves or inside the cylinder. Hmm, this could turn out serious.

Silicone cant dissolve in almost anything, so I would think it simply stays on the bottom or the top of the tank. That could explain why tests have not shown anything.

Apologies for the delay in replying after you guys have spent the time in trying to help but I have been away on business and hadn't had the time to make it back to the forum.

It has since emerged that the problem with fuel was indeed due to contamination with silicone.
However, I do not suspect the fuel to be an issue as firstly the problems have occured with fuel supplied in the south of England and I live in the north. Secondly, the engine runs just fine once it has started.

The only problem is with starting which is why I immediately suspected that one of more of the heater plugs had given up. When having changed all 4 of them didn't resolve the problem I wondered if the heater plug relay was malfunctioning and that's when I started looking for info or a wiring diagram to the relay so that I could work out which terminals to run a multi-meter across and at least eliminate or otherwise the relay as being the cause of the problem.... preferably before having to take it to a Renault dealer. But I guess that's what I'll have to do and hope that the car's computer tells their magic box exactly what's wrong.... otherwise, based on previous experiences and those of others, they will simply change one component after another until they hit on the right one.... and at ever increasing cost to me!

Martin

I've been putting up with the poor starting for a couple of weeks now as it doesn't start too badly from cold and eventually comes to life when hot but now I really am going to have to get to the bottom of the problem because it now won't start at all.

Just my luck as well.... it had started OK from cold, ran perfectly throughout the 20 minute journey and got all the way home without any problem but as it's broken down at home it really is my problem because I'm not covered on the breakdown or tow away cover if the car is within a quarter of a mile of home. Think I'll tow it up the road and then call out the AA!!

When trying to start it the heater plug symbol comes on, then goes out and is replaced by OK as normal and no other dashboard warnings come on except the oil pressure warning.
I had been beginning to wonder if it could be the TDC sensor but thinking back now the starting problems seem to coincide with me having bought a new power inverter to get a 240 volt supply for my laptop from the 12 volt power supply at the rear of the console between the two front seats..... just hope that it hasn't screwed up the car's electronic box of tricks.  :(

UPDATE

It wouldn't start again this morning but just before I hooked up the tow rope to drag it down to the Renault dealer this lunchtime I thought I'd try it again..... and it fired up!!

I took it down to the dealership anyway and they phoned later to advise that it needs a TDC sensor as well as a Cam sensor.... parts are ordered, pick it back up tomorrow and get relieved of another £250.

Martin

Hi Martin, the TDC sensor sounds very likely, they are very often the cause of problems. The cam sensor, I don't know... I would expect this to be a hall effect active sensor which doens't "go bad", but works until they stop. Unlike like the TDC pickup which is "just" the old style coil over a permanent magnet, and where it seems that the ones Renault uses are *not* very reliable.

- Anders

Hi Anders
I'd seen on the forum that one or two others have had problems with the TDC sensor so I half expected that one but really not sure that the Renault diagnostics system is so good that it can detect two faults at the same time!!.... and as you say it's likely that any Cam sensor (if they even have one fitted) is a simple Hall effect sensor which either work or they don't.
I am sure that you noted my cynicism.... but I can't help being suspicious about the supposed cam sensor especially knowing that this same dealer tried to charge a colleague for a diesel filter that they didn't change.

But we'll see tomorrow.... I may just surprise them and ask for the faulty parts and they can't use the excuse that they have to go back to Renault as the car is no longer in warranty!!

Martin

It is *possible* that both have failed, but I think it's more likely that it's the computer that is confused. The thing is that if one of them is failing, the computer can't know which one it really is. It would have needed a third sensor to know for sure.  Of course it has certain criteria that must be met before it claims a sensor to be faulty, and I would expect that "weak signals" or something similar would be one criteria on the TDC sensor, but as there's no such thing as a "weak signal" from the other sensor, chances are that the computer is just playing the game safely, if you know what I mean.

Besides, Renault makes more money that way....

I guess I'd require them to change the TDC sensor and reset the error list in the ECU. Then if the problem persists, replace the other one.

Getting the old parts is always a good idea.

- Anders

I did a bit more browsing Anders and found reference to a camshaft sensor within the G9T engine-specific service notes (3444A.pdf) in Lennart's vault.
It is indeed a hall effect sensor made by Electrifil.... but that is the only information about it that I have found so far.
Now that we know for sure that it is a Hall effect sensor then despite what the computer may be telling them it may well be worthwhile, as you suggest, getting the TDC sensor changed first and see if it cures the problem before changing the camshaft sensor.
I'll update you tomorrow.... thanks for your input Anders.

Martin

You're very welcome. I'll be looking forward to reading the next chapter here...

Hi Anders.... just to let you know that the Renault dealership phoned back to advise that changing only the TDC sensor cured the problem and cleared the fault code in the ECU.

But having collected the car later I'm still not so sure that it actually starts as well as it used when cold but it is certainly better than it has been when hot. However, I did also got more of an insight into what the diagnostic was telling them. It seems that it showed an incoherance between the TDC and Camshaft sensors.... or in other words the position of rotation of the camshaft didn't match with where the ECU expected it to be in comparison to the position of the flywheel. So that's why they'd said that they would need to change both sensors but the reality was, as suspected, that it was only the TDC sensor that was at fault.
So, thanks for your input Anders.... it was good to have someone to bounce off this problem.

Martin

You may find the cambelt has been replaced and not timed correctly.

I did wonder that myself George other for it having started fine for about two weeks after they'd replaced the cambelt and also once the engine is running it seems fine... same power etc. as before.
Also, if you believe what's on the job sheet from the dealer they re-checked the diagnostics after replacing the TDC sensor and all was clear so I guess that you have to assume that it's timed OK otherwise it would still be coming up with an incoherance between the flywheel and camshaft positions.
But then again did they actually repeat the diagnostics check or just fit the sensor and because it started then just forget it.
I'll see how I go with it.... at least it's now starting better when hot.

Martin

ouups - this reply was still sitting in my browser (for several days!) - good thing I never turn my laptop off these days :-)


Glad to hear you're on the road again.

My 2.2dci had the same fault. Apparently the connector for the TDC sensor is the most probable cause.

There is a specific note (vault:4324A.pdf) that deals with how to replace the TDC sensor, which eg says that the sensor indeed MUST touch the flywheel. I had to print that, and give it to my mechanic, before they believed it. The 2.2dci engine is not very common in Denmark, - only the Laguna was imported at all, and AFAIK very few of those were actually sold - hence their lack of knowledge/training.

Anyway, when my TDC sensor failed, I got the zig-zag fault symbol (and the codes stored in the computer).

Indeed, the computer reported discrepancy between camsensor and flywheel sensor, but the TDC sensor is almost always the cause (said my mechanic)
The TDC sensor is by far the "worst" placed of the two, as it sits open to the elements, under the car, however, it also means it is easily accessible - you can see it just by sliding yourself under the car behind the front wheels.

When our car acted up, it would most often start , but cut out some time later. When this happened, I could just wriggle the connector a bit, and off we go!

The repair kit has the TDC sensor and new wires, that are crimped in place - and I really hated the fact that they would cut the wires and make new joins - but as it is, it cured the problem, and we haven't seen it since.


/Lennart

Thanks for the info Lennart.... I checked the VIN of my car (JE0KL527759757) against those listed as likely to be affected by the problem sensor & connector detailed in the service bulletin but it appears to be outside the range.... mine was one of the last "real" Espace's supplied into the UK and I took delivery in November 2002.

Also checking out the part number of the sensor that is detailed on my service invoice (77 01 475 257) against the one quoted in the bulletin (77 01 474 895) it is a different part number!?

Quite surprisingly I haven't been getting any fault symbols... it just struggled to start or wouldn't start at all and after a while turning over the engine the oil pressure warning would come on but that's all. Once it did start it runs just fine and it has never cut out like you have experienced.

I didn't get opportunity this weekend to drop the undertray and take a look at what they'd supposedly replaced but did look under the bonnet only to find that they'd removed the air intake for some reason and hadn't replaced the spring clip that holds in place on the cast iron "doughnut" on top of the engine mounting so it was just flopping about in the engine bay. What is wrong with these people that no of them seem to have any pride in doing a job properly?

I've used the car a couple of times since getting it back from the dealer and it started OK but still not as well as it had always done for the last 4 years. But then my wife went out in it today and struggled to get it started at all... and had some strange things happen. On the first attempt to start it the seat belt warning light came on even though the seat belt was fully inserted so she turned off the ignition and tried to start it again but the second time immediately got the "Service" warning. She turned off the ignition and left it off for a few minutes to let it unscramble it's brains and on the third attempt it eventually started.

So all in all it looks like they have billed me £139.17 for curing a problem that isn't cured at all.

Martin

Oh no!

It's just not your day, I guess.

Could it be that they haven't fitted the TDC sensor properly (like Lennart suggests, it must touch the flywheel - strange!)?
Or a power supply problem. Perhaps as simple as a semi-dead battery...

- Anders

So did I, and my car was outside as well (September 2002)

Heh - a true French-car owner - not to be affected by its erratic behavior, - If you'll excuse my slightly modified Monty Python quote: "HA HA! - I spit in your general direction", - and try again - bingo ... :-)

lovely.

As Anders suggest, maybe they also did the wrong thing, and bent the clip "so the sensor didn't completely touch" ?

My garage did that out of their general experience, - and honestly I think I would have done the same. It seems wrong to use a sensor which needs physical contact, even if it is a hall-effect thing.
When I gave him that 4324A note, he raised his eyebrows in surprise, and bent the clip back into shape.

He has however never been trained on the G9T, which excuses him a little.
(very few, if any G9T Renault cars were ever imported into Denmark)

The Renault mechanics in the UK should be trained, so there is little excuse for them not to follow the very clear directions in that note.

PS: You don't have to drop the undertray at all, - the TDC sits open to the elements at all times (which maybe explains its problematic behavior) - just slide your corpus under the car - about under the front footwell, - and remember to bring some light.  Have a look here:
  http://www.matrasport.dk/Cars/Espace/Gallery1/Med/tdc_g9t.html

/Lennart

The only Monty Pythonesque thing I've felt like doing with it Lennart is giving it a good beating with half a tree  ;)



Easier said than done with a belly like a bay window ..... but I got the car jacked up high enough this evening to see that the flywheel sensor had been replaced and was butted up against the flywheel. However the connector had not been changed... the harness is complete and original.

Unfortunately I don't think I'll  have time to get them to take another look at the problem before I head off again.... just hope that it springs into life on Thursday morning when I have a 04.30 start to Manchester airport and again after being parked for week.... otherwise I'll be more than hacked off after arriving at 01.00 after an 8 hour flight.

Martin

Hmm, - well if it plays up again, try massaging that connector. If that helps (consistently) then you have found the problem. 
You can also try to (carefully) bend the legs in the connector, to tighten the connection somewhat.
However, on my car, I think the problem was the wires going into the conenctor, and not the connector itself, as I tried tightening it several times, while waiting for the sparepart to arrive.

/Lennart

The saga continues.

The Espace was parked at the airport for over a week and at 2.00 in the morning last Friday after an 8 hour flight from the Cape Verde islands via Banjul I was not in the mode for it not to have started....  luckily it did but only after having cranked over for nearly 3 minutes.
I already had it booked in at the Renault dealer for this Monday having previously relieved me of £139 for a TDC sensor that didn't cure the problem of poor starting, especially when hot.

I continued to use it over the weekend as little as possible but had to be out in it on Sunday afternoon only to get stranded because it would not re-start at all.
To me it has seemed more like a fuel issue than an electrical problem but I can hear the low pressure pump working as it should for up to 30 seconds or until the engine starts. But being stuck I had to call out the breakdown recovery people. The first thing he did was put some charge back in the battery then have me try to start it whilst he hit the EGR valve with a wrench in case it was sticking......... just shows how often they have seen that issue on the 2.2dCi engine in an Espace or Laguna!!!
"If it isn't that then it's a problem with one of the sensors or a fuel issue" he declared and then asked where I wanted to take it once he got it going because it would need a dealer / diagnostic check.

He then uncoupled the air intake after the filter and had me turn it over on the starter whilst he squirted easing fluid into the intake pipe and it immediately fired in to life. He therefore also suspected a problem with the low pressure fuel supply and noted it on his sheet when we dropped it off at the Renault dealer.
I phoned the dealer first thing Monday morning to advise that the car was already there and to suggest they check the delivery of fuel from low pressure pump..... but it's still in there with no sign of them having actually determined what the problem is yet.

So, I'll have to report again once they find a techician that actually knows anything about cars as opposed to ones that only seem able to plug in a magic box and replace parts but are completely stuffed if the magic box can't tell them what to do.

Martin

I can feel your pain, Martin. Sadly I don't think I have any positive input... except I'm amazed that your assistance guy knew that much about the car, seems like you should ask him to fix it..?! Not the abysmal Renault garages!

I think that the breakdown and recovery guys see more of what the problems are on particular vehicles than the dealers in any case but the big difference seems to be that they are much better at providing on-going staff training as well as disseminating information so that they all have access to a comprehensive knowledge base.

Also, squirting an alcohol or petroleum based vapour into the air intake of a diesel to get it going is fairly common practice. I remember learning to pour a bit of petrol into the air intake of an old tractor to get it going when I was kid and that was 35 years ago but the same technique works today even with the modern engines. Old diesels only used to have mechanical fuel lift pumps and if the battery or the pump was a bit tired it took a while before there was enough fuel to get it going so a shot of a more volatile fuel helped kick it into life long enough for the pump to start delivering sufficient fuel once the engine was running. Even for the modern engines with sensors and engine management systems it can still do the trick because by the time the computer has got it's brains into gear and determined from the many sensors that there should be a problem its too late because the engine has already started.

But it's now the fourth day that it's been in the Renault dealership. They telephoned on Monday afternoon to say that they "think" it is a fuel problem but they hadn't resolved it so could they keep the car another day. They haven't bothered calling me again since... I've had to call them and each time I get the same.... "we think it's a fuel problem but we are still working on it"

My patience is running out. If I hear nothing more from them I'm down there this afternoon with a can of easing fluid and will take it somewhere that hopefully knows what they are doing and can be bothered keeping their customers informed.

It should be just a 15 minute job to put a pressure guage in the fuel line to determine whether the low pressure electric charge pump is delivering the right pressure. They can also check the flow rate by collecting the fuel in a calibrated vessel and can even control it all from the diagnostic box without having to have someone else turn the ignition on and off but most Renault dealers seem incapable of doing even the basics other if something happens to come up on the diagnostic box.

Martin

Latest news.

I went to the Renault dealership yesterday to get to the bottom of what they had done to the car, if anything. I got all sorts of excuses and told how they were so stacked out with work (so many Renault's going wrong) and eventually discovered that all they had actually done in 4 days was to connect the diagnostic box and determine that the computer wasn't showing any fault codes... nothing more.
So there was no wonder why they didn't bother phoning me with any updates. The guy then proceeded to try to tell me that the starting fault and the TDC sensor they replaced 2 weeks ago were two different issues and that I'd have to pay between £159 and £215 for a fresh diagnostics check plus the labour and parts if any were required to fix it... but only when they eventually got around to looking at it!!
I don't know how I kept my composure but politely pointed out that having a problem starting was the reason it came in last time and they changed a sensor, charged £139 but it was obviously not the sensor because the car still has the same problem starting.
They thought that they "may" get around to looking at it today so I asked them to call and let me know what was happening. As anticipated I didn't get a call this morning so armed with a can of easing fluid and a screwdriver in case it needed a bit of manual fuel injection to get it going I went and collected the car.... needless to say I didn't pay any bills and have instead booked in at another dealership next week for them to take a look whilst I'm away in Helsinki on business.

I just love that car when it's going well but are they a nightmare when they go wrong... but it almost always seems to be because of the dealers being totally useless.

Martin

Oh dear...:(

How can a dealership be so useless..?! It really scares me.  :o  :-\

Hope your trip to Helsinki will be a good one. Just remember to sauna a lot, and drink a lot of that beautiful beer!  8)

Don't think I'll need a sauna.... because I'm already steaming.

Yesterday I washed all the oily hand prints off the bonnet and mucked out the floor well from where they'd got in with filthy boots and without putting down the paper as most garages do.... then I looked under the bonnet and saw something strange..... my driveway below the engine!
They knew that I was going to pick up the car but the knob polishers hadn't bothered re-fitting the engine undertray!!!

Martin

Gets worse and worse... :(  :-\

I feel for you Martin. Best of luck (you'll need it!)

After almost 3 weeks the Espace is still in a Renault dealership and they still don't know why it has trouble starting.

The first dealer had it for a week, put the diagnostic box on it only to find that there were no fault codes and then couldn't tell me when they would get around to looking in to it further.

Having pulled it out and taken it to the smaller but independent (not part of a big group) Renault dealer where it has previously been serviced they are still scratching their heads after 2 weeks. I was hoping that they would have solved the problem whilst I was away on business in Helsinki for a week but it's dragged on another week and now looks like being next Monday before they have yet another crack at finding out what the problem is.... at my expense of course with a further 3 hours labour at £64 per hour!!
At least at this dealership the first thing they did was come out to the car and experience for themselves how poorly it started whilst hot and at the same time covered the seat, steering wheel, gear knob and handbrake lever.

They've had it on the diagnostic box whilst starting it from both hot and cold but without any fault codes even though it struggled to start. The battery is fine, the low pressure fuel pump is delivering fuel through the filter so they started to suspect the high pressure pump.... but like I said to them... if the problem was with fuel delivery into the rail from the high pressure pump then why was the engine running absolutely fine once it started? In my humble opinion if the high pressure pump was on it's way out then surely there would be other symptoms such as poor acceleration or lack of pulling power if the pump wasn't delivering sufficient fuel.
It seems as though there is some leak-off of the fuel pressure somewhere... presumably back to tank as there are no visible fuel leaks. So the next move is to pipe and guage up the fuel system to see if they can determine if and why fuel pressure is dropping.

I wonder if either or both the fuel pressure sensor or regulator are monitored by the ECU? If not then they could be at fault but wouldn't show up as a fault code......... but then as with the high pressure pump if there was a fuel delivery issue why doesn't it show up in poor acceleration or pulling power?

The only other thing that I have thought of is that the fuel system is drawing in air from somewhere. I remember from a previous day job that one of my engineers found a very small split in a fuel pipe on a piece of construction equipment. It was just sufficient for air to get in to the fuel system to make it difficult to start but because the return line could easily accommodate the return flow of fuel back to tank there was no leakage of fuel from the small split in the feed pipe.

It's doing my head in... not to the same extent as the brain haemorrhage I had 2 years ago... but then similar in some ways as it looks like taking 5 hours to find out what the problem is which is the same amount of time I was in the operating theatre. Just hope that the Espace doesn't need £6000 worth of platinum coils to plug up a hole in a pipe!!!!

Martin

Hi Martin,

I hope your car will be as well as you seem to be! We are all happy you are here with us!  :D

It sounds like the garage you are now working with is a bit more professional. It does seem to be a difficult problem though and since I have very little knowledge about the high pressure diesel engines I don't think I can add anything. I would make a list of possible causes first though, and work systematically through that. It may be that something interesting shows up on such a list. Resolving the problem by unsystematically trying to replace parts they think may be faulty, is silly.

Try sending a mail to Roy Gillard from the Matra Club who is the Espace technical advisor and very experienced (if you haven't already). Address is here:
http://www.matrasport.dk/pointers.html#clubs (http://www.matrasport.dk/pointers.html#clubs)

- Anders 8)

Good of you to say so Anders.... I guess that I was just lucky to have a small brain in a big cavity so it would seem that little harm was done  ;)   
And the only indication that I had undergone any procedure was a very small scar where they went in to the femoral artery in my groin before using imaging systems to navigate their way up into my head from there. I was obviously out of it when they packed out the aneurysm with platinum coils but it was a bit disconcerting having them go back in to my head the same way a year later for a check up.... whilst I was awake  :o

Anyway... that's getting off topic. I had heard about Roy and his level of knowledge and expertise but hadn't contacted him. I'll try sending him an e-mail just to see if he has any previous experience of such a problem.

thanks

Martin

Hi Anders, 

Roy took a look at all the symptoms and came up with a number of very pertainent points.... one of which was to carry out a leak off test on the injectors which is exactly what the dealer planned to do but didn't have the special tools. The kit is on order and should arrive with them tomorrow so hopefully we should know more by close of play tomorrow with a bit of luck (and over 3 weeks without the car!).

I just hope that it turns out to be an injector and not the high pressure pump if they do find that the pressure is decaying.

Interestingly Roy advised that even if it had just been a cold start problem due to a faulty heater plug then simply changing the plugs may not have necessarily resolved the problem as the ECU needs to be programmed to be told that new heater plugs have been fitted!
Also, each injector is individually calibrated and the injection ECU has to have the calibrations recorded in to it so just changing the injectors needs an ECU re-configuration.

Will post an update as soon as I get any feedback.

Martin

Hi Martin

Yes, Roy knows a lot about these cars and has both experience and knowledge to understand how and why components fail. He is quite gifted.

I have also coupled his experience with my own garage's work with excellent results.

The comment about the ECU needing to know what has changed is interesting. I am personally feeling that there is something we don't know since the ECU is not reporting a problem - yet, the car won't start. For some reason, the ECU is ignoing a condition that would normally result in a fault code being raised, but we don't have enough information to say what.

It's good though that your garage seems to work systematically on the problem. My fingers are still crossed!

- Anders 8)

The Renault dealer workshop supervisor phoned and asked if I was sat down.... when I said I was he added that it may be worthwhile strapping myself in to the seat!!

They had found, in addition to Number 4 injector leaking off, that the high pressure pump is delivering  only 22 bar whilst the engine is cranking and it should be between 100 and 130 bar!!

So they are suggesting that I have all 4 injectors replaced (on the understandable basis that if one has failed the others may not be too far behind) plus new pipes, as well as the high pressure pump.... all of which would mean relieving me of £2300.

Quite surprisingly the price of the high pressure pump is less than £300 (but plus VAT of course) but it's the injectors at £244.16 each plus VAT that really crank up the total cost of the repair

So now I have some thinking to do..... swallow hard, dig deep and get it sorted.... trade it in.... or hope that it starts well enough to off-load it.......... but I'm just not the sort of person who could sell it to some
unsuspecting person knowing what was wrong. And I really don't want to trade it in... firstly because I just love the car and secondly because the new Espace isn't a "real" Espace just another steel and plastic box... and not a particulary nice looking one at that... in my humble opinion.

Maybe I'm paying the price for using supermarket sludge instead of proper diesel.

Martin

Urrgh... sorry to hear that. At that price I'd do the pump and only the leaking injector. Yes, the others may fail at some point, but perhaps it's JUST a problem with that single injector. I don't know how much labor would cost though...

I suppose you'll be writing to Roy to hear his opinion...?

It sounds like the starting problem was really down to the pump and not the injector...

I don't know about diesel qualities, but I would think that the fuel filter would be sorting out most of the problems. I think your problem is just an unfortunate mishap, and not something you can blame on anyone or anything. Bosch, perhaps...

At least your garage has diagnosed the problem now! That's a good thing.

- Anders

indeed you have - sorry to hear about your continuous bad luck. However as Anders says, at least they finally figured out how to do their job.

At that price, you are getting close to the point where you could buy a secondhand one from Autotrader, swap the parts needed, and sell the remains to a breaker ?

/Lennart

Oh dear... :( That's horribly expensive... :( I'd probably only change one injector too... but I don't know the full price-list of it.  :-[

Switching the engine might be another solution, as I looked into that earlier, and remanufactured engines range from £2K to £3K.... ::)

Before doing anything else this morning or making any decisions I first contacted Feather Diesel (www.feather-diesel.co.uk) to find out what they would charge for supplying the components.... out of curiosity as much as anything else because unless there was an absolutely incredible difference in price I would let the Renault dealer supply and fit the parts.... because as much as I want to keep expenditure to a minimum I do not consider profit to be a dirty word and the dealer has to make some out of parts as well as the labour (not only to cover general overheads but also the costs for training & special service tools)... but secondly, at least with parts both supplied and fitted by the dealer there is some warranty / come-back on the job.
 
Feather advise that they would first test the pump and injectors. The pump test would cost £157 and to test the 4 injectors would cost £110........... BUT...... to test the pump it still has to be removed so there is the cost of labour for doing that as well as for it's replacement, plus the pump to rail pipe, irrespective of whether the pump tested OK or not.... AND at less than £300 for a new pump from Renault they couldn't test and then refurbish the existing pump for less than it would cost to have brand new one.
Regarding the injectors.... the test can only determine whether or not the injector is working satisfactorily but if it's not working the test will not determine if the problem is mechanical or electrical and whilst they can resolve a mechanical defect they cannot repair a solenoid problem. So by the time you take account of the labour to remove the injectors, the new high pressure pipes required when re-fitting them plus the cost of a test it's more economical simply to go ahead and fit a new No.4 Injector and pipe.
They couldn't quote me exact prices for the pump or injectors because I didn't have either the Renault of Bosch part numbers and unfortunately the Bosch system didn't have the details even though I drilled down the system with him to get to a G9T 710 in a JE0K.... but he did say that the pump would be about £300 and the injectors over £200 each so pretty much in line with the prices quoted by the Renault dealer. Also, each injector is tested individually and data recorded that has to be programmed into the injection computer which then controls when and for how long the injector is opened using the individual parameters for each injector so Feathers may not have been able to do the job properly without the Renault diagnostic/computer box. As Roy pointed out in common rail diesels it's the injectors and the computer that does all the fuel metering and not the pump which simply delivers fuel under high pressure in to the rail. That's why, in relative terms the pump is quite low cost and the injectors expensive.
 
I later spoke to the dealer again advising that I simply couldn't justify having a £2300 expenditure but would sanction them replacing No. 4 injector and pipe plus the pump and the pipe to the rail but asked them first to change the injector and then re-test the pressure using the diagnostic computer as well as trying an alternative pressure regulator as Roy had suggested. Roy's opinion was that the low pressure reading could have been partially if not fully down to the injector leak off. He also thought that at only 22bar pressure it was unlikley to start at all but would certainly run badly....which it didn't once it was running. However, they were adamant that the pump is goosed and cautioned me that if the pump was breaking up then there could be particles elsewhere in the fuel system that could ultimately end up in the other injectors or the new one. They think that it's a particle from the pump that found it's way in to No.4 injector to cause the leak off problem and the reason for there being essentially two problems occurring simultaneously. It's also why they wanted to change all 4 injectors so they could ensure a clean system.
But I refused to have all 4 changed and instead asked them to save me the old pump so I could take it apart to help determine the extent of any risk I faced from further metalic particles.
 
I'll keep you posted as to any developments.

Martin

Hi Martin

I picked my Bosch Automotive Handbook (try Googling for it) and turned to the "diesel-engine management" section to look at how the injectors and fuel pump works. I've never before bothered reading about it, but I must say that it's really an incredibly simple system. The computer software probably isn't, but the system as such is...

Anyway, it seems that there's no filter inside the injector - petrol injectors have a small filter fitted that can be exchanged. So if there's metal in the system then it may get stuck in the injector, preventing full closure, or damage the nozzle or needle, or any other component in the injector. The injector is made in such a way that the solenoid and return spring actually doesn't provide the full opening force - it is augmented by the hydraulic pressure in the system.

In other words, the leak-off test sounds to be the correct way of diagnosing an injector. But since the others are okay, why should they go wrong? Because they are old? Perhaps, but since they are far more expensive than spark plugs on a petrol engine, I still think it's a good idea to keep the others, and besides, I don't think they are much more difficult to replace than the heater plugs (I know they are a pain to remove).

There is a fuel pressure sensor fitted in the fuel rail - it's odd that the computer hasn't detected the low pressure?

I don't know how little pressure the system can work with, but I tend to agree with Roy that if the cranking pressure is as low as 22 bars, then the running pressure should also be very low, and then I don't understand why the computer has not detected this?

I think by the way, that the relatively low price of the pump is affected by the fact that there has been several failures reported of these. Bosch had lots of problems with these, and I think Bosch lost a good deal of money on the common rail diesel systems back around 2000. Then they have probably increased the price of the injectors... the price of those sounds a bit silly.

- Anders

It's not necessarily the physical removal and replacement of the injectors that's the real problem Anders (although in the service bulletin covering the G9T engine in Lennart's vault it shows a special service tool) but it's the requirement for not only having access to but knowing how to use the Renault diagnostic and set up computer because each injector has it's own individual set of values that have to be programmed in to the injection computer. That is also why the suggestions, as good as they are, to obtain the parts from an accident damaged or scrapped vehicle cannot be practically pursued because I cannot realistically envisage a Renault dealer accepting to set up the computer after I've fitted second hand parts. And unless you could interrogate the computer of the car from which the injectors were removed how do you get the values that are required to be programmed in?
Are these just advances in technology or part of a well executed plan by vehicle manufacturers to ensure that you go back to an authorised dealer for almost all service work?


The computer can detect this from the fuel pressure sensor but it doesn't come up as a warning on the dash. A dealer can get the pressure reading by interrogating the car's computer system using the diagnostic box which is where they came up with the 22 bar whilst cranking the engine over..... but until they do the leak off test they don't know exactly why the pressure is low or where the pressure is decaying.

Just to give you a further update. I'd saved the filter that was fitted when the Espace had it's 72,000 mile service. So it has been on the vehicle for approx 3000 miles since the service and during the period when the starting problems manifested themselves. I had been wary of trying to open the sealed filter cannister in case I introduced contamination that would make it difficult to see if there was any pump debris but I took another look at it an decided to take a chance on trying to split it around the joint between the main body of the cannister and the cupped base. I ran a hacksaw all the way around but not all the way through the joint and then prised it open and withdrew the element from the body. There is no sign of any visible particles or debris trapped within the element but in the small amount of fuel residue that remained in the bowl I could see some minute particles... similar in size but not colour to the flecks in a metallic paint. However, these do not appear to be ferrous but more copper in colour as they glistened in the sunlight... so maybe phosphor-bronze from a pump shaft bushing rather than ferrous bits from the lobes of the pump vanes?.

I phoned the dealership again this morning to check if the parts were available from Renault stock and when I was likely to get the car back. The pump will arrive Saturday and they will work on it during Monday and Tuesday. I spoke to a different guy in the service department and he was really trying hard to get me to replace all 4 injectors saying that if I only had one replaced then don't come back to them in 6 months when it's starting badly again and particles have got into the other injectors. He also mentioned the insurance jobs they do when people have put petrol instead of diesel in the tank and it has wrecked the pump. He was saying how they have to replace both pumps, all pipework, all the injectors and the fuel tank to make sure that there are no particles left in the system. So I simply said to him that he had just answered his own question as to why I would only have one injector changed.... what is the point of changing 3 good injectors if there is debris in the system because without a complete clean out of the system the debris could get into the injectors whether they are the old ones or new ones. "I see what you mean Mr Tyas" he replied!! I then went on to reiterate that the only way we will really know how bad or otherwise any contamination is likely to be is to strip the pump once it's removed. So they are giving me a call on Monday once the pump is off and we'll split it, see what damage there is and make a decision at that point as to how far we go or otherwise.

Martin

Hi Martin

It's really good to hear that you've found a garage where they can actually communicate with their customers!

Yes, I think the injectors are precision devices - it probably doesn't take more than a few thousand nano-particles to change it's pattern a little with the pressure it is operating with, and further more, from how I understand the management system, it is running open-loop.

A (modern, my Murena doesn't!) petrol car uses an oxygen sensor to adjust the mixture, so a little difference between injectors doesn't matter much. From what I can read in the Bosch bible, there's no mixture sensing in the diesel common rail systems.

That means that the comptuer needs to know the opening times and flow numbers of the injectors - otherwise it will run the engine too lean or too rich.

The fuel filter is sitting before the pump, I would think that anything you were find in there would be coming from the tank and not the pump (if it's failing)?

But I really like your systematic approach to the problem!

- Anders

You are of course correct Anders.... however.... the fuel return lines, including the one returning unused fuel from the injectors go back to a manifold within the fuel filter housing before going back to tank via a heat exchanger to cool it down. So I thought it was worth checking whether the manifold in the filter housing was just used as a "junction box" for the return lines or if some of the returned fuel went through the filter housing before going back to tank.... in which case there could potentially have been some evidence of debris in the filter. Having opened up the fuel filter cannister I found that there is indeed a small (1.5mm) venturi within the return line manifold that allows some of the fuel back into filter housing. Whatever percentage of returned fuel goes into the filter housing through that venturi doesn't actually go back through the filter element but it does mean that debris from the pump (if indeed there was any) could possibly have found it's way into the filter housing and have settled in the bowl at the bottom.
So it was maybe worth a look inside the filter as I wouldn't have wanted to risk re-using it anyway under the circumstances even though it had only been on the car for 3000 miles.

Martin

Well finally after 4¹/₂ weeks and a bank balance lighter by £1430 I have back an Espace that starts as it always used to do.

They hadn't stripped the high pressure pump before fitting the new one but I got it back.... eventually!!!
I received all sorts of excuses that it was a service exchange unit and several other lame stories but I insisted that as it wasn't under warranty and the pump isn't service exchange and as I'd paid for the new parts the old parts were still my property. I don't suspect that it wasn't the cause of the problem but there was the principal involved as well as my natural curiosity to find out how badly or otherwise it had failed after 75,000 miles.

Hopefully I will get opportunity to strip the pump over next weekend and will let you know what I find.

Martin

Glad you got the car back Martin.... Sad you had to part with that much money!! :(

Keep us posted on whatever your research reveals!  8)

I tried to open the high pressure pump over the weekend but either the torx socket headed screws they use are as soft as grease or my drives are poor quality and don't seat properly... or both... because I rounded one trying to get one of the 3 pump heads off and also the smaller ones that retain the drive shaft seal housing. So at the moment I'm none the wiser as to the internal condition of pump. I'll get hold of some different/better torx tools, see how we go then and let you know.

The car is running and starting just fine now and I soon started to realise just how much I'd missed having that car. It was a lot of money to get sorted but it was worth it.

However... It will have to go back for some rectification work!
Instead of removing the air cleaner intake pipe from the spigot on the cast dohnut above the engine mounting they disconnected it from the air filter and simply swung it out of the way.... splitting the fabric pipe in the process.
Also the air cleaner housing was a bit loose and I guess that when they re-fitted it they didn't get it located properly as they pushed it back in to place and one of the 3 rubbber mountings was pushed out and is missing!

Anders... I got opportunity to take a closer look at the fuel filter and cut out the element so that I could open it out flat to determine if there were any particles in the folds but not a trace of anything. However with the filter element out of the way I could check out that little venturi I mentioned in an earlier post. Although two fuel return pipes flow in to a manifold on the filter housing before going back to tank it looked as though some returning fuel could go back in to the filter housing and so could capture some particals even if they simply settled as sediment in the bottom of the filter bowl and not through the filter element. However, upon closer examination it looks more likley that the venturi is there to provide a leak-off back to tank so a small amount of fuel would flow out of the filter housing through the little hole and not in to it as initially suspected. So, as you said previously the filter will only trap any particles coming back up from the tank.

I'll post again as soon as I can get the pump stripped.

Martin

I've only just taken a look at this thread so forgive the late input...
The following information is for everyone, and not specifically aimed at Anders - it's just that he quoted what many may be thinking.


No, it's nothing to do with that Anders.  Old type diesel systems used complex and therefore expensive fuel injection pumps that had to be accurately timed, but these new common rail injection pumps are very simple.  All they do is increase the pressure from the low supply pressure, to the extremely high common rail pressure (up to 1600 bar - yes that is over 23000 psi !!)  There is no need for them to be timed, since all the timing is done by the electronics.  Hence they are fairly inexpensive.


Again not quite right I'm afraid.  The new electronic common rail injectors are highly complex and extremely accurately machined items which have to work at these extreme pressure without leaking externally as well as internally which makes them expensive.  Furthermore, owing to mass production, there are still differences between individual injectors which although tiny, is enough that they now have a calibration that the injection computer will use to equalise the power in individual cylinders by altering the fuel amount and/or timing of individual injectors.  This is why the injection computer has to be programmed with the injector calibration codes.  These codes, by the way, are visible on the injector body, so even if you took an injector from another engine, you can see what code you need to input into the computer.  The problem is having the diagnostic equipment to configure the injection computer !

The very latest injectors (not fitted on the Espace) use a piezoelectric crystal stack for opening the injectors so that the response is so quick that they can have up to five openings per revolution instead of the one opening of the old system.  One opening gave a harsher engine as all the fuel for that cycle was injected at once.  These latest multi-opening systems, injecting smaller amounts in rapid succession give a smoother and quieter operation.  However, you can imagine the amount of processing going on to give a tiny pre-injection followed by up to four more small injections all in the space of milli-seconds !

These are the lengths the manufacturers are now going to, to meet emission regulations whilst giving the customers smoother, quieter, yet faster diesel engines.  Development is rapid as well as complex, and the garage trade is having even more problems keeping up.

Safety warnings: NEVER open a high pressure joint on these new common rail engines especially whilst the engine is running (danger to you) and never disconnect an injector electrical supply (danger of damage to the engine).

Oh well, thanks a lot for your input Roy. I didn't realise that they were that simple, actually.

Yes, the common rail diesel pressure is enormous really.

About the injectors, I actually don't think they are very complex devices as they consist of little more than a piston that can move, a solenoid to activate it, and small channels for the fuel to flow. By clever design of the channels inside, the fuel pressure is used to keep the injector closed and to open it, so the solenoid does not have to work against the enormous fuel pressure.

I am sure, however, that they are machined to extraordinary precision and tolerances are obviously very small. That may explain the prices of them, but it may also be that there is just a wide range of different injectors for different engines and models, whereas the fuel pumps are standard parts.

- Anders :)

I finally got around to getting some high quality TORX drives and opened the fuel pump that I'd insisted on having back from the dealer after they'd fitted the new one.

Anders, I've attached some photographs so that you can see what Roy was saying about how simple they are compared to the old style injection pumps which not only pumped but metered and delivered the fuel to each injector. The pump fitted to the 2.2dCi is a Bosch CP1 made in Italy and it has 3 heads/pistons only one of which is shown removed in the photograph.

Having removed all three heads I found no evidence of the pump having started to break up as the dealer had suggested would be the probable cause of both the low fuel pressure and a leaking injector that they thought would be as a result of being held open by particles from the pump. In fact, on the contrary, not only was there no sign of the pump failing mechanically but there was also very little sign of wear on the cams, the slippers or the piston as you can see from the pictures. The contact areas are evident on each of the componenents but no scoring or grooving.

Having said that the pump is simple it is nonetheless a piece of precision engineering that has to be manufactured to very close tolerances in order to be able to deliver the extremely high pressure. However, each of the 3 pistons are still a VERY tight fit in their housings. From a close visual inspection there seems nothing at all mechanically wrong with the pump components. There is the possiblity of course that the springs may be tired if compared to new ones but then that wouldn't account for the starting problem to occur so quickly. If the springs had deteriorated then I would have expected there to have been a gradual deterioration in the engine's ability to start.

The chances are that the only problem with this pump, if indeed there was one at all, is more likely to be one of the things that Roy had come across before and suggested they replace first which is the pressure sensor on the end of the pump.

I've thought about taking the pump to a Bosch diesel specialist I know to get their opinion.... the problem is that unless they put it on the test rig they won't be able to say 100% for sure whether or not it's OK and I would certainly need proper test results in order to be able to confront the dealer and that would cost £160.

Martin

Hi Martin

These are interesting photos indeed, thank you for posting them.
I agree it is a very simple device, though very clearly a piece of precision engineering.

In hindsight it should of course never have been replaced, and I know you were reluctant to do so. I think you should go back to the mechanic and tell them. You don't need a specialists opinion I think, as this pump is obviously perfect. First, they should know so they will learn, second you deserve a discount for the new pump. After all, it was them who told you to replace it, not the other way around.

It's worth a try at least, I think.

Cheers,
Anders

Despite the time, hassle and money there are two positive aspects to this saga Anders.

Firstly, I appear to be getting much better fuel consumption. I just filled up tonight and had done 625 miles (1005km) on the tank full and that was with quite a lot of local motoring. It was almost empty so it took over 77 litres but that equates to about 13km/litre. But before you say it I know that it will take a loooooong time to recoup the £1400 spent on getting it to start properly!

Secondly, now that I know that the pump wasn't breaking up I can at least continue to enjoy my Espace without the fear of contamination/particles finding their way around the injection system and causing further problems. I am also thankful for following Roy's advice in that I wouldn't agree to have the other 3 injectors changed at £250 each.

Whether or not I get anywhere with the garage remains to be seen but I will be letting them know.

Martin

Very interesting Martin. Keep us updated on the progress. :)

When I get a bit of time what I will probably try is putting the pressure sensor from the original pump in to the new pump on the car. It's fairly accessible without having to remove the pump or any high pressure pipes.
If the engine is then again bad to start it would tell me that it was only the pressure sensor that was at fault and not the pump itself..... and it would of course be much easier to go back to the dealer!

Martin