1999 Toyota Tacoma P0171 Reading

1999 TOYOTA TACOMA
110,000 MILES • 6 CYL • 4WD • AUTOMATIC
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JCMOORE4
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  • 1 POST
99 tacoma, took it to advance to get the check engine light read. P0171 reading. Replaced the O2 sensor before the cat. I haven't had the check engine light cleared to see if the O2 sensor worked. However after I replaced it, starting it seemed a little rough, while previously it was not really having any issues. Could not having the check engine light cleared cause this? What could other issues be?
Oct 26, 2010 at 9:34 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.
Oct 26, 2010 at 9:38 PM
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