Help with CEL? high idle...Thanks.

[win911]

Hi Everyone,

Well my 2001 C4 CEL went on today. Before it lit up I noticed that the idle was a little higher than normal. So I took out the handy dandy Durametric to see what it was...

Here are the codes it showed P0507, P1128, P1130.

So I went ahead and cleared them and started the car...idling eratic and check engine light went on again...

P0300, P0304, P0305, P0301... (mis fires).

I did a little research here in Renntech and all I saw was clean throttle body and check for intake leaks. I did both.. the idle did improve after cleaning the throttle body... but the idle is still a little high. Then....CEL back on with P0507.

Any idea? Thanks everyone in advance

[Loren]

P0507 Idle Air Control at Stop – Above Limit

Potential causes:

– Throttle valve is sticking

– Leaks in intake air system

[win911]

Thanks for your response Loren,

Questions?

When you say throttle valve? Is that the same as the throttle body?

Intake leaks... I'm assuming it would be between the air filter housing and the throttle body...right?

Thanks for your time.

[Loren]

Throttle valve is the throttle butterfly on egas cars (which your car is) - which is part of the throttle body.

An intake leak could be a number of places like a bad air oil separator, a bad o-ring on the oil filler cap or bad oil filler tube. A loose or broken vacuum line/hose etc.

[win911]

Hi Loren...thanks for the speedy response.

Okay, so I cleared the code once more. Check for any intake leaks.

Then... CEL back :o

P0300, 0306, 0304, 0305, 1128, 1130, 0507

I am assuming that since my idle is still high that I have an intake leak somewhere that's causing the lean reading, thus the 1128, 1130, and 0507... but how about the misfire in one side?

I do have a few more questions:

1. Do you have a diagram of the vacuum lines to check?

2. How do I know if the air/oil separator is bad?

3. The oil seals on the oil cap looks fine...should I just go ahead and change it anyway?

Thanks again for your help

[Loren]

Take the air cleaner off and the connecting tube. If there is a lot of oil in the intake then you likely have a bad AOS.

[win911]

Update:

It's been a couple of weeks and still NO CEL :lol: . All I did was clean the throttle valve, added Chevron fuel injector cleaner, checked for intake leaks (none), and changed fuel filter.

Thanks Loren and everyone for there help.