Code P0171 and P0174
Asked by GuruB68TZ Jan 22, 2019 at 09:35 PM about the 2007 Chevrolet Avalanche 2LT RWD
Question type: Maintenance & Repair
My 07 avalanche is pulling p0171 and p0174
codes saying the engine is running too lean. I
replaced the intake manifold and they still
show. I have a cold air intake on it (not sure if
it has to do with that) I need to pass
emissions to get my tag. Please help!
4 Answers
Crew_Chief answered 5 years ago
Cold air intake sounds like the problem. The engine is pulling more air in than normal, which is why the ECM pulled those codes. I would put the OEM intake back on in order to pass emissions inspection. Not sure whether the codes will affect you inspection status, but better safe than sorry.
Zyncplate1 answered 5 years ago
Had same issue found Cold air intake and k&n filter not really designed for MAF SENSORS. the oil from filter gunks up sensor. I was throwing both codes. Put OEM set back and cleaned sensor. Codes cleared as soon as i restarted car.
Same issue with k&n filter. Anytime you replace the air intake with aftermarket parts this could be an issue. I replaced my MAF because there’s 220 miles on my Avalanche. Found a good one on Amazon for $33.
