2.4l spyder gs rough idle

[805DSM]

Ok Just bought this 96 spyder gs 2.4 n/t with 99.xxx miles and all stock with NO CHECK ENGINE light on . The car was running and idleing good until afew days ago. I noticed it's running Rich at idle and the idle is lopey , drops to 450 then back up to 750rpm. I've done the whole maintanance on it an nothing has changed . Cheked for air leaks, broken/ripped vaccum lines and nothing .. THE CAR IS NON-TURBO so no I can't check for boost leaks.. And it's all stock , so what else should I check?

Thanks

Alex

 

[95strandedDSmR]

I just finally fixed a huge idle issue on my turbo 2.0 which was very lopey and unstable bouncing between 200-750 etc etc almost as if it souned cammed up, also smoked black smoke as if it was running rich.

Problem ended up being the exhaust cam was out of time by 1 tooth. So it couldn't hurt to double check your timing marks on the motor.


Simpler things to check would be IAC motor,and TPS sensor make sure they are both functional. They both adjust the idle and stability of the air coming through the throttle body into the manifold.

I assume you already did the "maintence" thing like you said, plugs, wires, air filter, fuel filter, oil change etc etc.

Could also check fuel injector o-rings. Im not sure how the PCV valve effects the non turbo 2.4 when its not functioning, but on my previous cars that were non turbo, a bad pcv has caused me some idle issues. Just some ideas hope you have some luck with it bud.

 

[805DSM]

I just finally fixed a huge idle issue on my turbo 2.0 which was very lopey and unstable bouncing between 200-750 etc etc almost as if it souned cammed up, also smoked black smoke as if it was running rich.

Problem ended up being the exhaust cam was out of time by 1 tooth. So it couldn't hurt to double check your timing marks on the motor.


Simpler things to check would be IAC motor,and TPS sensor make sure they are both functional. They both adjust the idle and stability of the air coming through the throttle body into the manifold.

I assume you already did the "maintence" thing like you said, plugs, wires, air filter, fuel filter, oil change etc etc.

Could also check fuel injector o-rings. Im not sure how the PCV valve effects the non turbo 2.4 when its not functioning, but on my previous cars that were non turbo, a bad pcv has caused me some idle issues. Just some ideas hope you have some luck with it bud.

Yeah , I changed the PCV valve and did all the maintanance on it, when I got it it would idle good and normal , then hear and there it would
idle rough then it go back to normal. Now it's just idleing rough and running Rich at idle. I just need to check the timing marks

 

[805DSM]

Its been a while. It ended up being a bad EGR Valve, it was stuck open so it got replaced and Fixed the issue.