2000 Ford F-150 Repair Question
Trouble code P0171 --System too lean (Bank 1)
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...
57,318 answers provided
Lean fuel condition could be caused by one of the following below:
2.EGR and PCV valve.
3.Low fuel pressure.
4.Dirty fuel injectors.
5.Mass Air Flow Sensor.
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