I have a p0171 code on my ford ranger 2.5 and have replaced fuel filter maf sensor, iac sensor, fixed vacuum leaks, replaced fuel filter, checked fuel pressure it was a steady 38, replace all o2 sensors, and replaced spark plugs and wire but the code still continues to come back on what is causing it? Also if this helps, when I rev the engine in park to 3000rpms and then quickly let go of the gas the car begins to shake almost like it going to die then after a few seconds ford back to normal
My car has 150000 miles.
My car has an automatic transmission.
Hello there. You might to read this article about the P0171 OBD-II trouble code; as it will give you ideas on causes and possible solutions.
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