Okay, I posted this elsewhere and I wanted to try here as well, here is what I have so far. My vehicle is a 2002 Ranger 4.0 6 Cyl, 75,000 miles.

Code 1:

P0171-Fuel trim bank one condition. Rich or lean condition detected by the oxygen sensor.

Code 2:

P0174-Fuel trim bank two condition. Rich or lean condition detected by the oxygen sensor.

If bank one and bank 2 are set together, suspect a fuel condition or MAF sensor fault

Other reasons say:

Failed H02521
Ingnition misfire condition
Fuel injectior problem
engine mechanical; condition
Oxygen sensor defective

So, likely since they both are in error, what is going on?

I did notice a stall yesterday, no light. Attributed it to the cold weather. Also, added fuel this morning and tightened cap later on today. Light still on after 15 miles, codes as above. It has been cold and the fuel was low, could I have a bad plug from water or something?

Ideas? Never replaced plugs but fuel filter and oxygen sensor at 30-40,000 from what I recall.


Additionally:

The truck had been in Buffalo for 5 years, which you know is cold. I am in PA now, but the temp with the windchill was 10F. Has been in colder conditions and not done this.

I know the fuel was real low on Sunday. Monday I got it filled up, no light until maybe lunchtime after I had driven it 20 or so miles from when I first got gas. I had the fuel filter replaced about 40,000 or so miles back. Could I have drawn in water and destroyed a plug or two? I have never replaced the plugs.

There is no acceleration issue that I can feel, no rough idle, no hesitation now.

So, what do I do now? Where would anyone here start?