P0170 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 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 large (The actual mixture ratio is too lean.), The ECM judges the condition as the fuel injection system malfunction and light up the MIL (2 trip detection logic).
Symptoms- Engine Light ON (or Service Engine Soon Warning Light)
- Excessive Fuel ConsumptionPossible causes- Intake air leaks
- Front Heated oxygen sensor may be faulty
- Injectors may be faulty
- Exhaust gas leaks
- Incorrect fuel pressure
- Lack of fuel
- Mass air flow sensor may be faulty
- Incorrect PCV hose connecPossible solutionDirty air filter of faulty air flow sensor are common causes of the problem. When is the code detected?- Fuel injection system does not operate properly.
- The amount of mixture ratio compensation is too large. (The mixture ratio is too lean.)
Monday, February 14th, 2011 AT 10:48 AM