My car threw this code today. Checked the air filter, and it wasn't too dirty, but it wasn't new, either, so I hit the parts puppies and replaced it, then erased the code.

Got about 40 miles on it now, no code.

Anybody else got any further ideas?

I think that was the code that BIllBoost was chasing around for some time. Finally fixed it by first cleaning and then replacing his battery cables and ground connections.

Might also have been caused by a plug wire touching the O2 harness.

That sounds so weird I just hadda go check, and yes, one was.

What'* up with that?!

p0171 lean code can also be caused by Low fuel pressure from pump. (I chased this code on my wife'* Envoy. No matter what I did (or replaced) It kept coming back. Finally, as a last attempt i replaced the fuel pump, even though the car ran good, always started and the pump ran quiet. That fixed it. The pump wasn't weak enough to cause a drivabilty problem, but was weak enough to lean out the motor enough for the PCM to detect it.

I hope that'* not it. The pump in there is only about 40K old.

But I'll keep it in mind. Thanks.

Hmmm. Maybe a fuel pressure check would be in order.

it ended up being my FPR thanks to willwren I didnt jump to conclusions about the pump
check your fuel pressure with a gauge...if its low replace your fuel pressure regulator before you buy a new pump

I think I'm OK there. Mine was replaced under a recall at about 90K. But I'll check all now. Thanks.

Bob... Search P0171 You will find that corroded (under booties) and loose battery connections was the culprit for a few of us.

Foghorn had suggested I check my negative cables, the FSM'* send you after electrical stuff first. Pump...while being possible is near the end of the trouble shooting. Understandably who wants to change a pump.

I'd start by pulling the battery cables..clean them well, look under the boots.. then the other end of all cables.

Go from there..

Odd how you toss me in your siggy and end up with my favorite code.

Who loves ya, Boosty?