Code : P0171
Make : 2004_TOYOTA_PRIUS
Description : P0171 2004 TOYOTA PRIUS Air/Fuel Mixture System Lean Bank 1
Possible causes :
– Intake air leaks
– Faulty front heated oxygen sensor
– EFI M relay
– Engine coolant temperature sensor
– Ignition misfiring
– Faulty fuel injectors
– Exhaust gas leaks
– Incorrect fuel pressure
– Lack of fuel
– Faulty Mass Air Flow (MAF) sensor
– Incorrect Positive
Solutions :
– Carry out a Reset via CarDiag
– Choose a better quality fuel
– Check that the tank cap is securely closed
– Check the oil level and add more if it is lower than MAX
– Restart an Automatic diagnostic via CarDiag
– If the fault persists, you can check the “Possible causes” listed above : visually inspect (by yourself (tutorials to come) or by a professional) the wiring harness and the associated connectors, check for damaged components, and look for broken, bent, pushed, or corroded connector pins.