Q: Here is the code to the check engine light, P0171- System Too Lean Bank 1

asked by on February 10, 2018

Here is the code to the check engine light, P0171- System Too Lean Bank 1
I already fixed the sensors recently and also checked to see if their was a leak. a few months back which the results were negative. I think I need to replace my air filter housing,
My car has 98619 miles.
My car has an automatic transmission.

A number of things may cause code P0171 or P0174 to be triggered. As the codes indicate, 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. These codes are also often times associated with misfire codes as well. 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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