Q: My car has the code p0171 and i fixed multiple things and cleared the code as well and it still shows up

asked by on November 01, 2017

I have changed all the parts. Erased the codes. And still have the codes appearing in less than 25 miles

My car has 191852 miles.
My car has an automatic transmission.

A number of things may cause code P0171 to be triggered. As the code indicates, this means there is a lean fuel condition which may be caused by a lack of fuel supply or in some cases, a vacuum leak. When a vacuum leak is present, this introduces an excessive amount of air into the fuel/air mixture which results in leaning out the fuel content. Other problems such as a faulty fuel pressure regulator, a faulty fuel pump, a clogged fuel filter, faulty fuel injectors, faulty oxygen sensors, or a faulty mass air flow sensor may also cause this to happen. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.

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