I posted a post on here yesterday about some codes I got on my Lexus IS300 that said both bank 1 and bank 2 o2 sensors where having a slow response. I didn't clear any of those code and went for a drive in it today and the codes were replaced with codes p0171 and p0174 that say that both my o2 sensors are detecting that my engine is running lean. I also have a problem with the EVAP system where when I pump gasoline into the tank the pump randomly shuts off like the tank is full and I have to press the trigger again which from reading online it could be something with the charcoal canister. I'm wondering if this problem could cause the engine to run lean? Or if not does anyone know what my problem is for it running lean?
Any vacuum leak including evap leaks can cause an engine to run lean but of course so can we fuel pumps clogged fuel injectors but do check for vacuum leaks first
@scottykilmer
Your vent valve is bad.....when you can’t pump any guess in your tank.