TDC - where? and how difficult is it to access? [Fixed!!]

[TheJoker]

Hi guys,

I've had a bit of help from Roy (thanks!!!) and if I've understood things right, my first port of call, for the intermittent starting and occasional hiccups, is the TDC (Top Dead Centre) sensor.

If I've figured this picture out, the location is not the easiest to get to.
http://www.matrasport.dk/Cars/Espace/Gallery1/Med/tdc_g9t.html

I need to get under the car, and probably remove the protective thingie under the engine to reach the sensor...?! Do you guys reckon this can be done on the street?! (I can't get my car into the garden and my garage is simply too small, even if I move the bikes out.)

And the recall..? What does the recall fix? Which part of the cable?!

I'm thinking of replacing the TDC sensor myself, if I can easily, and probably solder the cables with heat-shrink and so forth. Anyone know what the price of the TDC sensor is and/or part number?

I tried a local garage. Asked them if they could do it, and they didn't even ring back with a price... hrmph.... And ironically the car started (aided by cables) on the first try today, after two months of no uses. 

[Lennart Sorth]

If I've figured this picture out, the location is not the easiest to get to.

That picture was taken without removing anything on my 2002 2.2 dci, so provided you can jack up the car in a safe way (or is very slim, and have 5 joints in your arms) it is quite easy to get at.  This is probably also one of the reasons for the common problem ... the elements have just as easy access.

And the recall..? What does the recall fix? Which part of the cable?!

The recall - or "technical note" ( http://www.matrasport.dk/Cars/Espace/vault/JE/4324A.pdf ) cuts the old cable, and crimps on the new sensor. I'll second that whatever extra protection step you can think of is appropriate. Double the number of crimps, grease and wrap the whole thing in heatshrink or similar etc etc.

The note also specifies that the TDC must be pushed to actually *touch* the flywheel - something my Renault garage overlooked the bastards. But they ended up doing the same repair free of charge a year later for that reason.

Anyone know what the price of the TDC sensor is and/or part number?

not off my head, but it is not very expensive. I'd guess under 50£. The labor to have it fitted at Renault is far more. However, I know Roy has replaced enough to have several good ideas as to how to make that repair last, and given the choice I'd hand my car to him anytime.  (but my Espace is in Denmark, so I have only been able to benefit from this once - and that was a nightmare job of a clutch master cylinder replacement, - a different and long story)

/Lennart

[TheJoker]

Thanks Lennart! That clears most of my confusion up. I had a look at the GSF Car Parts site and there's two of them there (don't know if they're for the 2.2 dCi), but the price was less than £20. I think I'll visit the Renault garage and see what they want for it and might come home tomorrow and replace it.
Roy's a busy man. I'm glad for any help I can get.   

[Martin Tyas]

The Part Number for the TDC Sensor I fitted on my 2002 2.2dCi is 7701477748 and was £22.08 plus VAT from my local Renault dealer.
If you give them the VIN or registration number they can check if your vehicle already has the latest connector (which mine had) or if you need the TDC sensor kit to include the wiring connector upgrade. The sensor supplied by Renault has with it some guidance/information notes and diagrams to help with installation.

Replacement of the TDC sensor is a DIY do-able task but the higher you can raise the front of the vehicle on axle stands the better. Also you may find that removing the left hand front wheel will give you easier access by sliding yourself under the car from the side rather than going under from the front.

Martin

[TheJoker]

Thanks very much for that information Martin. The price definitely seems right for a DIY job. I've got axle stands, but their lifting capacity is obviously limited to my trolley jack's capacity.

Roy already checked whether my car had the fix, and there's no record of it being changed. Which leads me to the next question; can I visually check if it's been done or not?! Or should I yank the cable off, then rush to the Renault dealer with the part and let them assess it..?!
I'm actually not concerned with the connector as long as I can simply solder the cables together. I'm hoping that they'd have the same colours or at least something that would allow me to determine which cable goes where.

Thanks again! 

[Martin Tyas]

If it has been updated with the latest connector/sensor but outside of the Renault dealer network then you should still see evidence of the revised connector having been spliced on to the original wiring harness... but you may have to open up the plastic cable protection sheathing to see if/where the new section of cable has been added. The sheathing is normally split along it's length so is quite easily opened up once you've removed the tape from the end where the two wires to the sensor protrude.

As an alternative to going under the vehicle twice (especially if your local dealer doesn't happen to carry the TDC sensor in stock) you could always get the sensor kit that includes the modified connector and fly leads then you are covered whatever has or hasn't previously been done to your vehicle..... if it already has the latest connector then you simply replace the sensor with the new one without needing to install the cable & connector from the kit and if it hasn't been modified then you already have all the components needed to complete the job in one go.

By the way the sensor kit from Renault also comes with a new spring steel retainer for the sensor as well as the new sensor itself and if the connector doesn't need replacing then it will take you longer to get the car on to axle stands than it will do to replace the sensor.

Martin

[TheJoker]

Much appreciated, Martin.
I went to the dealer before having read your reply and the result is the part number you had too; 77 01 477 748. It cost me £23.63 + VAT which is £27.19. I got the sensor and the bracket you mentioned.

Attached () picture shows a blurry version of what I got. I'm a bit worried that it's the cable that's screwed and that I'll have trouble getting the connector, but I guess I could cut the cable off, and put in new cables using the original connectors or something. Worst case I'll have to go to the garage and get the cable.

[TheJoker]

Right gents.... £31 later and the Espace is up on two Halfords ramps. I've crawled under the car and I have unplugged the cable to the TDC sensor. It's dirty, but I wouldn't say that the cable looks to be a problem. I will however, clean it up tomorrow when it's light outside.
The problem I'm having though is that I have no clue on how to remove the sensor!  I can turn it in the retainer clip, but that's it. How do I pull it out? Or do I pull it out?

Also the adjustment. You said it should touch the flywheel??!  Surely not? My current sensor is, from looking at it in the dark and my memory 1-3mm away from the flywheel. But I could be wrong.


"Luckily" the car did play when we attempted start up to drive it up the ramp.  Let's hope this fixes it.

[Martin Tyas]

The sensor is held in place by the spring pressure created by the retaining clip... so you need to press on the clip to release some of the pressure produced by the "wings" of the retainer and the sensor should then slide out. Depending how long yours has been fitted it may be that the retainer has created small grooves in the plastic housing of the sensor so you may have to rotate it from side to side at the same time as pulling on it. That's why I mentioned about getting the car up as high as you can so that you can get under easily enough to get both hands on to the job.... one to press on the retaining clip to release some pressure whilst at the same time using your other hand to twist and pull on the sensor.
It does go back together with a new sensor and clip much easier than the removal.... trust me

Regarding the proximity of the sensor to the flywheel. I seem to remember reading somewhere that the distance should be something like 2mm but can't recall whether it was on a technical note or on the sheet that came with the sensor from Renault. Did you get an installaition guide with the sensor?
If not then I'll take a look and see if I kept the one that came with mine.

Martin

[TheJoker]

Thanks Martin. Makes sense with the clip. I knew it would be some sort of kung-fu grip to do it. I didn't get anything else than what's on the picture above. Hence me waiting till tomorrow morning when there's light out to fix it so that I can clean things up under there and make sure everything is OK.
If you, or someone else, can let me know the distance from the flywheel then I'd appreciate that. Otherwise I'll just stick it back in there same distance as it was.

Thanks again!

[Martin Tyas]

I've had a look through my Espace paperwork in the house and also my parts stash in the garage.... I thought that I'd retained the old TDC sensor and clip along with the guidance notes that came with the new sensor but unfortunately it looks like I binned them after fitting the new sensor.

The sensor head does need to be in very close proximity to the flywheel. I'm sure that I pushed the sensor against the flywheel and then eased it back 2mm. There is often a bit of "run-out" on the flywheel so its worth turning the engine through a full revolution to ensure that there are no high points that still touch the sensor after you've eased it back. If you can get someone to help and have the vehicle on axle stands rather than ramps then you could try putting the car into gear and rotate one of the front road wheels in order to rotate the engine without actually firing it up whilst you are underneath and trying to look for and hear any fouling of the flywheel againt the sensor head.

Sorry I couldn't be a more help with the guidance notes.... but hope you get it sorted

Martin

[TheJoker]

Martin, very kind of you to look through your parts and paperwork. Very much appreciated. I do have axlestands, but I can't get the car high enough with my trolley jack, and I feel safer under the car using the ramps. I'll see if I can turn the engine somehow - it is a high-compression-diesel so it won't be easy. Perhaps starting the engine, and crawling back under would be OK. If I screw it up I'm sure that I can live with paying another £27 for a new sensor. 

Anyway... filling myself with coffee now whilst waiting for the temperature to rise a few degrees and the frost to thaw on the car.... brrrrrrr.... 

Thanks again!

[TheJoker]

It seems to be working!

Very many thanks to both Lennart and Martin for the tips and encouragements and not to forget Roy who has been very patiently analyzing my emails to come to the conclusion that first port of call would be the TDC Sensor.

It was quite a doddle to do once the car was high enough to access the area. I took a few pictures of the cable, and I'll post that later and I was hoping if you could help me and have a look and see whether the recall has been done or not. To remove and replace the sensor you do need both hands. One to press the clip towards the sensor and then the other hand to pull / push the sensor.
I cleaned things up around there a bit. I also tightened the oil pan just a touch as it was leaking a few drops. I don't know if that will have made it better or worse, but some of the bolts were quite loose. I then WD-40'd the connecotrs etc and put it back.
The car then showed OK sign on first try.  Sadly the joy was a tad dampened by the low oil level light (car was on ramps and I haven't checked the oil in quite a while). A dash more oil and it all seems fine. The battery was quite drained so we used cables to fire the engine up. I took the car out for a spin and it all seemed fine. I have since the sensor change started the car a dozen or so times without any engine error problems. I'm currently charging the battery too, but I had to move it and it fired up as perky as ever.

New TDC Sensor; £27
Ramps; £31
Working Espace; Priceless!

I'll return with the picture and a status update once I've ran the car a bit more.  Thanks again!!

[Lennart Sorth]

It seems to be working!

That is SUPER news - congrats!   I do remember the great feeling of (slowly) growing confidence by seeing that nice 'OK' sign at every start :-)

However, the sensor distance to the flywheel is particularly mentioned on page 13B-2 in the recall note to "butt up to the flywheel".

I assume any slight movement of flywheel (or uneven surface) will eventually push the sensor out to where it JUST clears the flywheel (as with brakepads and disks).
However, using this method ensures you don't leave more space than absolutely necessary. It is a rather weak hall-sensor signal, and as with any signal processing, you want the largest signal possible leaving the sensor to limit the influence of noise and poor cables.

/Lennart

[TheJoker]

Thanks Lennart. I wish I had trusted your initial post about pushing the sensor to the flywheel.  I guess the best thing for me to do is to drive the car up on the ramps tomorrow and "just do it" now when it's all fresh in my memory. 

Thanks for your help!