P0171 CHEVROLET - 2003 impala

Question

p0171 code o2 sensor checked,new plugs ,wires good,i did clean maf sensor with carb cleaner,but the light was already on....what can i check now...it seems to run fine

Answer 1

Hi there,

The P0171 code indicates a lean fuel mixture on bank 1. This could be caused by an intake manifold leak or some other vacuum leak on this bank. The P0131 code is for the bank 1 sensor 1 O2 sensor. If you don't find any intake leaks, replace the sensor. It can cause the P0171 code if it's no good.