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Q: P0171

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I had a p0325 and p0171. I fixed the knock sensor but the lean bank 1 is killing me. I have replaced the MAF, PCV, FRONT O2 SENSOR, found one vac leak and replaced hose. STILL HAS P0171, What am I missing? HELP!!!!!!

My car has 188000 miles.
My car has an automatic transmission.

A: The code P0171 is due to the left bank of t...

The code P0171 is due to the left bank of the engine running lean and has reached the rich limit for the ECM. Try to have the injectors cleaned and run only high quality fuel that has cleaning additives. This should clean out the injectors and combustion chambers and clear the code. If you need help having this done, a certified technician from YourMechanic can inspect the code in person to determine the appropriate actions.

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