Dang and everything was going fine. I have a 96 Z with CAI, LTs, 1.6s, a few other bolt on and afermarket stuff.

Just this morning halfway to work it starts idling rough with a pop in the exhaust. Never happened before. O2s are only a few months old, opti is a year old. Runs well in high rpm, just not at idle and flutters if I make a slow take off from idle. I did a search, just wanted to see if there was some new ideas or solutions. Thanks guys.

 

Fuel filter maybe? That seemed to make a big difference when i repalced it. I think it was like $9 from Advanced Auto.

 

Hadn't thought about a fuel filter. It hasn't been 10k since it was changed with the pump. It feels more electrical or sensor somehow.

 

Sounds like O2's though. Are they Bosche? If so then i am sure it's them. Under WOT you engine ignores your O2 sensors and runs on predetermined A/F tables. I believe that is called OPEN loop.

 

No they are AC delco straight from Chevy. I have had bad O2s before and this is not the same. Bad 02s usually give me a pig rich start, sluggish behavior, etc. This is different. Not to say it isn't, but just don't think so. Thanks for the replies though.

 

I'd say definately change the fuel filter. It will only take about 3 minutes. Just unscrew the gas cap to relieve pressure. Dont worry about any of the other crap they tell you to do. Loosen the screw end first then remove the slide end. I'm sure you already know how to do it though. As far as idle i would say remove the rubber elbow attached to the TB and spray in some TB cleaner. Could just be that you have alot of carbon build up on the TB or something simple like that.

Also you might want to try some Sea Foam. I love the stuff. It always seems to make a difference. I prefer Guaranteed to Pass Emmissions for injector cleaner, you could just use denatured alcohol, but you might wanna try to clean the injectors. That Sea Foam will help to clean out your intake and combustion chamber.

 

Talked to a friend at the dealer and he said it sounded like EGR. I was able to stall the engine at idle by depressing the valve, so what does that mean? I have the EGR programmed out with LT1edit. Could it still be the EGR?