Poorly GTA

I think the diagnostic light would be on if the engine management system has detected a fault with any sensors and was substituting default values. I presume that the diagnostic light is not on when the engine is running (and of course that it works and has not been "disabled" by any previous owners who couldn't be bothered sorting a duff sensor).

Injectors all fire at the same time - not sequential.

I wondered if it might be your MAP sensor but just been out and disconnected the pipe to mine and if anything, the car revs more freely, if a bit erratically, but does not cut out at 2000rpm.

Hi Simon,

Yes i am beginning to think along the same lines, but in my experience of EFI cars fitted with MAP sensors, if the cam timing is out then the engine will not idle at all and when you pick up the throttle it will misfire but you can rev through it and the mis will clear!
Mine is the opposite way around.

When i did the cam timing i went by the marks on the chain as i didn't have a manual, and when i started the car and it fired up first time i thought all must be ok!!????

Hi Michella,

The diagnostic light doesn't work at all so i will have a look at it tomorrow.

If i can sort it out and then the light doesn't come on with the engine running then i guess i am looking at a mechanical fault!??

The diagnostic light will tell you if a sensor or the wiring to it is broken or if the sensor is providing a suspect reading (god knows what it considers suspect though). I guess that sensors can be providing readings that are wrong but within tolerance and the light will not come one. The only way to diagnose in that instance is to rent David Gentleman's engine diagnostic reader. That will tell you the running values of all the sensors.

I trust you have found the engine manual in the technical section of this site -it has instructions on how to set and check the cam timing.

I am having trouble downloading the manual for some reason,(i'm not all that good with computers)!

Do you know if the A610 is set up in the same way??

When the cam timing was out on mine after having the head gaskets done, it would start and idle ok and even drive quite well and was still fairly swift until I got somewhere over 3000rpm, when the engine would feel strangulated and just wouldn't rev anymore. I couldn't get past about 5000rpm. Perhaps it's something to consider still.

EDIT:

Actually, reading my old post, the idle was lumpy when the timing was out.

Might be some useful information here to help diagnose possible symptoms if it is the cam timing:

http://www.renaultalpineownersclub.com/ ... highlight=

I have just spent all day doing the cam timing.
Bank A was one tooth out and Bank B was two teeth out, i'm surprised it ran at all!!!

Why do Renault put marks on the chain when there is no apparent use for them?

Even though the marks on the chain lined up when the engine is at TDC it obviously is not the way to do it when you consult the manual!

Oh well i have learned something else today,just the exhaust to go on tomorrow and then i can hopefully say all is ok!!!???

Hopefully that's sorted your problems. Let us know how it runs.

Ah, thats where you need a Haynes manual or Autodata timing sheet for the Renault V6, as Im pretty sure both of them tell you to IGNORE any timing marks on the chains....but likewise, the original manual tells you how to time up the engine, with no mentions of any markings to follow..

A610GA (Geoff) had a similar problem, the car was running pretty well but he thought it was a buit down on power... turned out one of the cams was 30 deg out!!! the other had a GTA cog instead of a A610 one...
Was about 100hp down on power!

I was saying to Geoff the other day, the problems with the V6 is they are not an interferance type design (ie, pistons hit valves) when the timing is out...

Now, this may sound like a good thing, but think how many GTAs that are out there, probably not timed up correctly and the owners don't realise. It least if the pistons hit the valves, you'd know you done it wrong straight away....

I think it is quite common for low compression engines (and consequently turbos) to be non-interferance.

I think it is quite common for low compression engines (and consequently turbos) to be non-interferance.

You'd be surprised, many modern turbo engines clip valves when timed up incorrectly, or the timing belt snaps. They run higher lift usually than our old V6's..

SUCCESS!!!!!

Just taken the car out for a spin and all is well.

A big thankyou to everyone who helped me out,i can now hopefully enjoy some trouble free motoring!

Just a quick question regarding boost.
On the guage it goes to about halfway in third gear under load,is this normal?

Looking back through the history of the car it shows that the ECU has been chipped,where on the guage should it go to if this is true?

I would like to put a normal guage on it and try it on the road but unfortunately it doesn't seem that straight forward!?

You cant judge your levels by the standard guage, for a start theres no scale and secondly its a GTA guage so its probably inaccurate!!! Fitting another guage is simple, the most difficult bit is running the vaccuum pipe through the car from the engine bay. Having said that you can now get them with remote senders so you would only need to run a wire through. If its been chipped, presumably you have a bleed valve?