- May 16, 2014
- 8
My wife's '04 4.2L I6 trailblazer has started setting the P0171 lean on bank 1 code. I am trying to determine if this is too much air or not enough fuel. I used my reader to clear the code and look at fuel trims at idle with the vehicle warm. The LTFT is solid at 8.2% and the STFT oscillates between +5% and -3%. The RPMS are around 600.
While driving, the code will be set and the RPMS will go to around 900 at idle and will not return to 600. If I clear the code, they will immediately drop back to 600 at idle. I also noticed that if at idle with the code cleared, when I turn on the AC compressor, the code will immediately be set and the RPMS jump to 900+.
Any advice on how to determine if this a lack of fuel issue or too much air issue?
While driving, the code will be set and the RPMS will go to around 900 at idle and will not return to 600. If I clear the code, they will immediately drop back to 600 at idle. I also noticed that if at idle with the code cleared, when I turn on the AC compressor, the code will immediately be set and the RPMS jump to 900+.
Any advice on how to determine if this a lack of fuel issue or too much air issue?