Strange cold idle + lope

[Duo Chan]

Well, the Camaro's finally giving me some problems, after 70k miles. Not sure what's up, but that's why I'm asking the experts!

The car's a 98 Camaro, 3.8L with a SLP CAI and Whisper lid and Magnaflow cat-back exhaust. Lately, when the car is started cold, the RPM runs high, around 1,500 RPM and lopes, the car shakes and steams/smokes quite a bit. After the car warms up enough for the computer to enter closed loop, it runs nice and smooth, around 700 RPM idle.

Also, at times, when trying to accelerate from 60mph to 70mph, around 2,000 RPM, the engine wants to lope and lose some power.

It just had a tune up that did not cure these problems. New plugs, plug wires, fuel filter, complete fuel system cleaning, oil change. Any advice would be openly welcome!

[CDNFB]

Re: Strange cold idle + lope

I'd start with a compression check of each cylinder and then I would look at fuel delivery. Sticky injector(s), or dirty injector(s) with poor spray paterns. Also check fuel pressure.

[crushedout]

Re: Strange cold idle + lope

Might want to check the Mass Air Flow, do you have a SES light?

[Vanquish]

Re: Strange cold idle + lope

I would check the injectors as well, and also even though you mentioned that you just changed the fuel filter, you might want to take it off and see if it's hard to blow air through it. Even though it's new, you may have gotten a little bit of bad gas after you got the tune up, and it is causing the problem.

Or possibly, you could be running a little rich due to a bad fuel injector, but usually even after the car warms up it will still idle bad, so I don't believe that could be the problem. Just thinking out loud. Good luck with finding and eliminating the problem.

[Duo Chan]

Re: Strange cold idle + lope

Thanks for the replies, and sorry I haven't checked up on the thread for awhile. Been a busy week.

Negative, it isn't popping the SES light at all.

The MAF, I'll check out. Not sure if the mechanic touched it at all, due to me telling him not to F-up my CAI. :P

The fuel filter will probably be later on my list of checks, because the car was doing this long before the tune up which changed the filter.

I'll take all the comments to heart. Thanks all!

[auto666]

Re: Strange cold idle + lope

make sure your battery connections are clean and tight i know it sounds dumb but it can do it:banana: