I have had the check engine light on my car for about 6 weeks, and cannot figure out what is causing this. the code I am getting is P0172 (bank 1 running rich). But the Mv on the O2 looks to be slightly rich, but nothing really abnormal. The short term fuel trim bank 1 (computer correcting factor), states 3 thru -3 which is perfect, it fluctuates like it should. I checked for vacuum leaks, and found nothing. The fuel system holds pressure properly and duty cycle is working properly. I have a KB BAP, and i disconnected it from the system, to see if the pressure switch was in the ON position all the time, and it is working properly as well. I do not want to spend money on stuff that is still working properly just to guess what is going on. If there is anything that I can check, voltage, or disconnecting anything in the system to see if I can narrow down what the issure is, then please let me know, I am stummped at this point.:shrug:
