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Q: What can it be?

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Got my starter replaced yesterday now my engine light is coming on. Took it to auto zone and got code: p0171 fuel system too lean. Help!! i have no clue what this could be.

My car has 133600 miles.
My car has an automatic transmission.

Hi There, This code relates to your oxygen sensor detecting a lean fuel condition in the exhaust gases. Generally this will apply to either "bank 1" or "bank 2" which indicates which side of the motor the problem is coming from. In some cases this may apply to both. What this means is that there is not enough fuel present in the air/fuel mixture being burned in the motor. This is often times caused by things like faulty fuel injectors, a vacuum leak, a faulty or dirty mass air flow sensor, an exhaust leak or potentially a faulty oxygen sensor itself. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.

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