i have an 02 WRXand one day im driving along normaly.... not beatin on it... and my CEL comes on.... so i check the code... reads lean on bank 1... the car ran fine... then one i was driving and i gave it like half throttle and around 4500rpms it would hesitate... then it threw the same CEL code.... what could this be? I have a cat back exhaust and a BOV...
first things first....welcome to the club. Got a P0171? How long have you had the bov and what type? Might also want to make sure all your connections and seals (bov) are okay. If you have recently added the bov and still have your stock one then put that back on. Yes, the bov may make the car run rich during shifts, not lean...but ya never know. Also might want to make sure your MAF is clean. Another thing to consider is a faulty O2 sensor. once you determine all the above is okay, then reset your ecu and see if it comes back. just my .02 good luck
Well with that CEL it usually means that your long term fuel trim is pegged at +25%. The first two things I'd check for are intake leaks between the MAF and the turbo and then to also clean the MAF with an electrical contact cleaner. Is your BOV at atmospheric one? If so, did you plug the recirc hose on the turbo inlet? That's probably the culprit if that's the case.
Yea so i got the problem figured out!!! it was that BOV... i put a stock one back on and the problem is gone!!! thanks alot guys!!!
