high idle

2003 CHEVROLET TRAILBLAZER
87,000 MILES • 2WD • AUTOMATIC
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SUNCRAIG
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I have a 03 chevy trailblazer and i have replaced the O2 sensor 3 times. System lean comes up on engine check. What is the problem? I cleaned the throttle body, changed the fuel filter. i did notice a rattle on start up around exhaust manifold. Just frustrated cuz the trail blazer has so many sensors and i dont have a clue.
Jan 17, 2011 at 3:16 AM
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RASMATAZ
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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.
Jan 17, 2011 at 10:58 AM