P2178 – System Too Rich Off Idle Bank 1

 

P2178: DIY Repairing Video Tutorial

https://youtu.be/4qOSQ24kgus

Check out nonda Auto DIY Center for more engine error code repairing videos.
https://www.youtube.com/playlist?list=PL-Lyko0O0oxHe1AGvzwAz-wokJPXAtW97

 

P2178 Possible Symptoms

  Engine Light ON (or Service Engine Soon Warning Light)  

P2178 Possible Causes

  Intake air leaks,Faulty front heated oxygen sensor,Ignition misfiring,Faulty fuel injectors,Incorrect fuel pressure,Faulty Mass Air Flow (MAF) sensor,Incorrect Positive Crankcase Ventilation (PCV) hose connection  

P2178 Description

  With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the theoretical mixture ratio based on the mixture ratio feedback signal from the heated oxygen sensors 1. The Engine Control Module (ECM) calculates the necessary compensation to correct the offset between the actual and the theoretical ratios. In case the amount of the compensation value is extremely small (The actual mixture ratio is too rich.), the ECM judges the condition as the fuel injection system malfunction and light up the MIL (2 trip detection logic).