I've searched on this and turned up a BUTTLOAD of data. Here's the deal:
This weekend after getting my oil changed and replacing my headlamp assemblies (which involved removing the battery, thus resetting my PCM) I suddenly found myself with a CEL. The codes are the P0171 and P0174 (too lean on both banks).
After researching this, I've decided it would be really freaky to loose 2 O2 sensors at once, and I just cleaned my UIM about 8000 miles ago and haven't had a vacuum leak at all since then (new gaskets, the works, except I didnt' replace the fuel pressure regulator). So I'm figuring either it's a dirty MAF, OR it's a problem with my fuel delivery system.
I also wanted to mention that I'm getting GREAT gas mileage with the CEL, and the engine runs cooler. In fact, she runs just below the N in NORMAL. But I do seem to notice a slight loss of power at WOT, but it may just be a plecebo effect.
I'm going to try cleaning my MAF with electronics cleaner today, but I'm wondering if it's that Fuel Pressure Regulator I never changed or possibly the fuel pump? I mean the car DOES have 104k miles on it :/
How do I test for proper fuel pressure?
Last edited by rkneeshaw; 05/04/03 01:29 PM.
