Anyone have anyideas here? 1998 Avenger V6. Was tuned up last week-end been doing fine till today. Died and wouldnt start for an hour or so then ran fine but "check engine" on.
AotoZone just checked it P1391 code. their printout is hard to read. Then on way back here light went out and it still runs fine. Any help would be appreciated.

 

I've NEVER seen a four digit CEL ....
Here's a listing ...http://asog.net/content/view/23/25/

 

AutoZone printout has the P, guy said 1391. Their printout under Dodge says ECM detected intermittent reading of CMP or CXP. Under Mitsubishi says intermittent loss of CMP or CXP.
I'm assuming those mean cam position sensor or crank position sesor. Now its fine and light went ou on way home. Think I saw on here thats its usually CMP and that its in the distributor?

 

All the "P" codes are a 4 digit number

You have either a cam position sensor or a crank position sensor going bad.
If the cam position sensor malfunctions then the car "in theory" should still run, you just loose sequential fuel injection, the computer does not know which rotation to fire the injectors, but it will still run.

If you loose a crank position sensor signal then the engine will not run at all. So i would try replacing it first if the problem comes back. Its a lot cheaper than the cam position sensor that is in fact located in the distributor.

 

Ive got the cps testing pinned above ...

 

Thanks guys, we'll try that first then. Sons car, I'm just along for the research and work. LOL

 

if your car is missing at a certain RPM then it is your CKP (crank shaft possition sensor
) i had the same problem and it fixed it right away. the cam possition sensor only fixed the problem a little bit. so to be on the safe side just replace them both. they are inexpesive and easy to do. just be careful taking out the crank sensor they like to break off in the block!!! as i have experienced!

 

Well, did a tune-up and crank position sensor. Runs like a top now and so far no problems. Thanks all.

 

The code I had was p-1391. It would only run poorly when at full operating temp. when at a stop light the engine would idle at 400-500 RPM and would want to die. I replaced the Idle Air control (35$) Since the torx that hold this to the throttle body face the firewall it was pretty easy to take the throttle body off first then remove the IAC. With the throttle body off, I gave it a good cleaning with Q-tips and throttle body cleaner. So far the truck is running Great. Thanks for all the tips and advice.