The Definitive Engine Code P0171 Diagnostic Handbook

The ECM has the power to adjust the amount of fuel injected if an increase in the amount of air being fed into the engine is detected. However, ... After doing some Google searches, I found that code means air fuel ratio is too lean. So the measured af ratio has less fuel/more air than what ... A trouble code P0171 or P0174 means the oxygen sensor or Air-Fuel Ratio (AFR) sensor (in bank 1 [P0171] or bank 2 [P0174]) has detected a lean ... It could be lean under high load/demand conditions and fine at low load. Mixture lean/rich codes can't set until the O2 sensors are active and ... The DTC indicates that the oxygen sensor on the first cylinder bank has detected lean engine conditions. This means that there is too much air or not enough ... Car less than 2 weeks old - Engine Malfunction - P0171 code (System too Lean Bank 1) ... Searching this forum yields no other mention of p0171 ... p0171 code (lean bank 1) ... The O2 sensor only cuts in (closed loop with ECM) once the engine has warmed up and coolant temp has exceeded 158F/ ... The check engine light came on after I washed the engine. I did not use high pressure. I just used a scrub brush with soap and cleaned everything real good. The P0171 OBD-II code means that, on the first bank of the engine, the fuel system is running weak or a vacuum leak exists near this side of the engine. The P0171 error code indicates the engine is running lean. The powertrain control module (PCM) monitors the oxygen content of the exhaust post-combustion.