Can a tune cause lean codes???
#1
Can a tune cause lean codes???
Getting lean codes on both banks. My pcm is tuned for 58# fuel pressure, my avalanche engine is one of a few that runs on 50# from the factory. I have found no way to increase fuel pressure { no fpr that holds 58# will fit my rail }. I have tried everything else that will throw lean codes and found nothing. I drove the avalanche with no codes before I did the conversion.
#3