bad93z

I got my longtube install done last weekend and have been noticing that my car is running rich now, and I've noticed that my MPG actually dropped a bit. I've got an LT-4 knock module to throw in it (doing that tomorrow) but what else can I do? I also removed the cat, egr and A.I.R. and expected to get a SES light but didn't. Do I need to get my car tuned for these changes or will it be fine with stock programming?

Thanks in advance
Clint

stereomandan

If your car is running rich, then you may have an exhaust leak. Can you hear a pfft, pfft,pfft.. when you give it medium to full throttle? If you do, then you probably have an exhaust leak. This will allow air to get in the headers before the O2 sensors. The PCM will add fuel to compensate creating a rich condition.

Headers work fine on the stock tune.

Dan

Edit: I looked at my post again and fixed something that I had wrong. I said that the PCM will add air if you have an exhaust leak. Duh, I meant fuel. Sorry if I confused you. I fixed it now.

bad93z

I tightened my bolts again yesterday. The car does have an exhaust leak, although it doesn't sound like its at the head, but maybe at the slip fit connector for the #1 primary tube, or at the collector.

Thanks for the advice