idle problem after belt change

[shawnvic]

have just changed timing belt on 99 jeon 16v,car starts but idles roughly,have checked all settings and all still in line.if i rev the car the engine sounds ok,its just on idle.having found some more info about inlet cam crown wheel having to be immobilised"no movement left and right"mine had some movement  but could not insert cam lock tool at correct position so had to move it to get tool in place. anyone any ideas on this,thanks

[Anders Dinsen]

You got it running since your last post, i assume?
It sounds like the cam is slightly off. Are there any position marks on the cam wheels to ensure they are all in line?
It's hard to say, but there could be a few things, I suppose.

[roy4matra]

have just changed timing belt on 99 jeon 16v,car starts but idles roughly,have checked all settings and all still in line.if i rev the car the engine sounds ok,its just on idle.having found some more info about inlet cam crown wheel having to be immobilised"no movement left and right"mine had some movement  but could not insert cam lock tool at correct position so had to move it to get tool in place. anyone any ideas on this,thanks

If you could not get the camshaft locking pin in, as it wouldn't line up, I suspect you had the crankshaft locking pin in the wrong hole.  The crankshaft web has some balancing holes and one is often close to the timing pin groove, and many people get the pin in the balancing hole rather than the timing groove.  This puts the timing slightly out and the camshaft does not line up.

You may have then compounded things by moving it to get the tool in, and the timing is now slightly out which is why the engine is not right.  We get a number of vehicles brought in to the workshop for this type of problem after attempting to do it themselves and getting it wrong.  Please remove the belt and try it again checking very carefully.  The fact that it was fine before and the fault has only appeared since the belt change, says the fault has been caused during the change.

Roy

[shawnvic]

still not right but only a slight missfire now,the saga so far....crankshaft definetly at tdc,camlock inserted easily, rotated enginge by hand still lines up,problem arises when turned over by starter inlet cam (dephasser)jumps approx half a tooth,if rotated to tdc crank pin goes in, exhaust sprocket in line but inlet sprocket(dephasser)is slightly out so cant insert cam lock,have taken belt off and on about 10 times still same result,could it possibly be inlet camshaft sprocket at fault by not being able to lock it in place,anyone any idea of cost.have read that the inlet cam should be immobile but mine has movement each way ..

[roy4matra]

still not right ... have read that the inlet cam should be immobile but mine has movement each way ..

The dephaser should be tight and not move, except under inj. computer control, so if yours is allowing movement, you need to replace it.  These have been a problem for some time, Méganes commonly had failures, and it is the dephaser not the control solenoid.  The solenoids rarely fail in my experience.

Roy

[shawnvic]

thanks roy any idea of cost,it dosnt look to bad a job to change.

[roy4matra]

thanks roy any idea of cost,it dosnt look to bad a job to change.

Not sure about costs as I haven't done one myself (us diagnosticians leave the actual work to a mechanic after we have diagnosed the fault!)  However, you will need to remove the cap to get at the dephaser nut to the camshaft.  This needs a Torx tool and is very tight - I've seen many damaged or broken and then you cannot remove them without a chisel and having to replace them afterwards.  Also if you buy a dephaser, you need to check it is locked before fitting - many came unlocked by mistake and caused further problems!  You need to hold it in a vice and rotate it back to make sure it is locked.

Roy

[shawnvic]

thanks roy ,locked old dephaser ,car running ok as far as i can tell,still have problems with control solenoid i.e. car sounds like a diesel  when warm.is there a way to test it i have unplugged it but it makes no difference.was thinking of going to breakers to aquire another to see if makes any difference,are they standard on f4r engine laguna megane etc.thanks again roy

[roy4matra]

thanks roy, locked old dephaser, car running ok as far as i can tell, still have problems with control solenoid

Why do you think you have dephaser control solenoid problems?  They rarely give problems in my experience.  If your old dephaser wasn't locked, then it will have been worn, damaged or broken, and it probably needs a new one.  This is probably why the car sounds wrong.  The only way to check properly is on the Clip where you can see if the valve timing is altering correctly.  Since it is the inlet valve timing that the inj.computer is altering via oil pressure controlled by the solenoid, and increasing or decreasing overlap, if this is wrong in the slightest way the engine cannot run correctly.  If you unplug the control then the dephaser can only remain at idle setting and the engine definitely cannot run properly!  It will not produce any real power as you need the increased overlap.

If it is truly running correctly, then the control cannot be faulty.  Or you have unplugged something else!

Roy

[shawnvic]

dephaser changed ,new bolt and end cap fitted,you was right roy the old dephaser bolt was really tight but a long bar soon shifted it.car running better than ever thanks for your advise roy.also car no longer souds like a diesel on tick over when warm.parts total was only £123.

[Anders Dinsen]

Congrats!