2005 buick lasaber starts backfires when given gas and dies

Question

Cleaned mast sensor replaced crank sensor had 0336 and 0171 codes starts ideals give gas abt back fires RUNS rough and dies help

Answer 1

Hi there

This sounds like an issue with the mass air flow sensor. This is mounted on the throttle body, and when it's reading wrong the computer will try to make the correct fuel mix. This could also lead to the p0171 code you had. This is a long term fuel trim code for a lean fuel mixture.