Trouble code P0171 --System too lean (Bank 1)

2000 FORD F-150
105,000 MILES
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HARDOG013
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What does this code & discription mean
Nov 10, 2011 at 10:50 PM
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JACOBANDNICKOLAS
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The air fuel ratio has more air than it should and not enough fuel. It could be the result of an O2 sensor, a vacuum leak...
Nov 10, 2011 at 10:52 PM
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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
Nov 10, 2011 at 11:47 PM
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BMDOUBLE
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The most common failure for this code is the PCV tube elbow on the back of the throttle body or on the valve cover, depending on which engine type you have.
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Apr 8, 2020 at 4:22 PM