2001 GMC Sonoma P0171 CODE 2001 GMC SONOMA 4.3

2001 GMC SONOMA
109,000 MILES • 6 CYL • 2WD • AUTOMATIC
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LVMARK
  • MEMBER
  • 1 POST
MY SERVICE ENGINE SOON LIGHT COMES ON OCCASIONALLY AND HAS STORED THE CODE
P0171. I CAN,T FIND ANY VACUUM LEAKS AND THE VEHICLE HAS MULTIPLE OXYGEN SENSORS. FUEL
ECONOMY SEEMS TO HAVE DECREASED A BIT.
SHOULD I REPLACE THE OXYGEN SENSORS AND IF SO, WHICH ONES? THANK YOU
Jun 25, 2010 at 1:31 PM
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RASMATAZ
  • ✓ASE Certified Mechanic
  • 75,992 POSTS
  • ASE Certified Mechanic
Lean fuel condition could be caused by one of the following below:

1.Vacuum leaks
2.EGR and PCV valve.
3.Low fuel pressure.
4.Dirty fuel injectors.
5.Mass Air Flow Sensor.
6.Oxygen Sensor.
Jun 25, 2010 at 2:13 PM
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