My Camaro keeps throwing a code for a lean bank 1, what could possibly cause this? I have a very slight exhaust leak due to an EGR block off plate not sitting perfectly, but I'm not sure that could cause the problems I'm having. If I try to take off quick it studders and hesitates, but can cruise around town okay. If i drive uphill it'll surge, making the RPMs jump up and down a couple hundred every few seconds. Its just an odd problem that I'm hesitant to start throwing money at, so any input as far as diagnosing the problem would be greatly appreciated. Its a 1999 3.8l v6, bone stock other than the EGR delete.

 

Seal your exhaust leak first. When a cylinder fires the exhaust pluses between pressure and vacuum. An exhaust leak will allow air to enter the exhaust system during the vacuum phase. The computer will try to add my fuel because the O2 sensor is seeing more oxygen. The computer will not set the code until it decides it can not fix it with adjustment and it will put the car in LHM (limp home mode) AKA open loop. The end result is a car that runs like crap.

Having the exhaust leak for any amount of time could cause a lot of other issues but step one will be fix what you know is wrong. Might want to think about plugs because yours have been running to rich. Normally I would say clean them but they are such a pain to get at just replace them.

 

The exhaust leak has been sealed, SES light is gone now but the surging and hesitation is still happening. Is it possible it could be a MAF sensor or TPS sensor issue?

 

check your plugs and 02 sensors for fouling, can cause issues if they are all carboned up an black