My lt1 will run fine for about 3 or 4 minutes then will start to run real rough. After about 5 to 10 minutes of this the check engine light will come on. A couple of minutes after this it will run smooth again with the check engine light still on. It will stay running smooth until I turn it off and let the car cool down. The same pattern is repeated. ANY ideas!? I cant figure this one out and am baffled!

 

Anyone?

 

Well obviously the first thing you do, before asking us what's wrong, is ask the ECM...

 

Scan it and let us know the code that it throws, sounds like my problem kind of, does the check engine light come on right as the fan comes on?

 

Yes the fans do turn on when the check engine light comes on . I dont have any tools to scan it with and was trying to get some ideas for me to try before paying a shop to diagnose it.

 

Goto your local parts store. They usually have a scanner to do it free. I think even places like Tires Plus do scanning free. Idea behind that is they scan it, tell you the problem, and then figure you'll let them fix it. So if you do, just tell them you'll think about it, that sounds a bit pricey. Some excuse

We definitely need the code to help you. The Check Engine light + Fan problem is just how the ECM works. Redundancy if you will. Incase something fails, the fans come on so it won't overheat.

 

Thanks for the advice, I think thats what ill do!