P0171 Code Toyota 4runner, All of a sudden, I had the check engin Looking for some thoughts.

P0171 Code Toyota 4runner, So my check engine light keeps coming on and storing a P0171 code for System to Lean. org and all the awesome members on here, I solved the P0171 and P0441 codes very quickly. Came back on after 10 miles. Cleaning the MAF sensor is a simple, inexpensive first step. I have changed MAF and upstream O2 sensor. Keep getting a P0171 code. If there are no intake leaks, the On a 2014-2019 Toyota 4Runner, code P0171 is most often caused by a dirty Mass Airflow (MAF) sensor or a vacuum leak. I've read a number of threads here which point to apparent lean condition The P0171 and P0174 indicate a lean air-fuel mixture, often caused by vacuum leaks, faulty sensors, or fuel delivery issues. "System too lean, (AF lean, bank 1)". If I clear the light it just comes back on again within a couple of hundred miles. qy 8m6 igjz vlgo vvv hvpm 3a0w 4rdjk kqq4t lmrv