Join Date: Jan 2007
Location: Southern Ca
Car: 00 OB 07 OBXT
Feedback Score: 0 reviews
Fuel Trim Malfunction is the code.
The computer can't rationalize the info it's getting from the sensors.
I'd say check for intake leaks, exhaust leaks, clogged injectors, fuel pressure, clogged fuel filter, etc. Most likely the Front O2 sensor needs to be replaced but ... Full tuneup Including plugs, wires, PCV [clean or replace, possible cause of vaccum leak], Clean Throttle body/IAC, Fuel filter, Injector cleaner in tank. That gives you a good baseline to work from and helps eliminate many factors that you would have to guess at when trying to figure it out.
Rear O2 is basically just for smog purposes, the front one is integral in calculating fuel trims.