2016 Chevrolet trax

[Kycowboy]

I have a 2016 Chevrolet trax that has a p0171 code I have changed both 02 sensors, mass air flow sensor, fuel injectors, checked for vacuum leaks and it still has the code

[autojoe]

4 cylinder? How about low fuel pressure? How did you check for vacuum leaks? Do you have a scan tool capable of reading fuel trims stft and ltft?

[silicon212]

Check for unmetered air ... check PCV hoses, check your intake tube, check it all. Everything from the MAF to the cylinder head. The P0171 happens because the PCM has detected a lean condition and has trimmed out. This is almost always due to unmetered air (air which enters the system behind the MAF). Vacuum leaks are a big source, but it can happen before the throttle body too.