please look at files

[Dynoguy]

Please take a look the car bucks indiscriminatly . has started ideling at 3500 when cold, eventually idles at 1250 when warms up

[RayD]

Have a look Here in the meantime ...

Ray

[GeoffSmith]

There are possibly at least three problems you need to resolve before trying to get a stable tickover: Your thermostat appears to be stuck open because as soon as you start off, the coolant temperature temperature drops towards 0°C. You should not get boost under these conditions (but you are) so your wastegate could be sticking (check the Wiki). Your O2 sensor would not appear to be working either. I would recommend you sort these problems then check your base timing and then you might be able to set the tickover and get the engine speed to match the target idle.

[Dynoguy]

Thanks, I understand how to set idle.

I was providing the fact that it when from stable to this new behavior of idling high and oscillating as a symptom to help identify what has gone wrong. I will check the wategate, the thermostat is relatively new. Any chance it is the CTS sensor itself? The car does warm up quickly.

Since it idled properly before, and it started this behavior all of a sudden, I am loath to start messing with timing etc. To me if I figure out what went wrong it should go back and idle correctly. I may be wrong. Thats why I am looking for the voice of experience on this board.

Roger

[RayD]

Thanks, I understand how to set idle.

Sorry Roger, I wondered if it might be something simple like a vacuum pipe being off.

Does it idle at normal speed in service mode?

Do the revs increase when you remove a vacuum pipe?

Ray

[Dynoguy]

Thanks Ray, I fixed some vacum leaks and it helped immensely. I will see what happens in service mode and I have ordered a thermostat.

Roger

[RayD]

You’re welcome Roger, let us know how you go on.

Ray