I have engine light on and diagnostics shows P0420. What to do.
Dec 26, 2007 at 8:26 PM
2003 Toyota Corolla Engine light P0420
2003 TOYOTA COROLLA
VAQASKHAN
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code for poor catalyst efficency on bank 1
An oxygen sensor is no more good and should be replaced
The engine coolant temperature sensor is not working properly (change it first and see if code comes back)
Damaged exhaust manifold / catalytic converter / exhaust pipe (visually check over, if this and the first 3 come up negative change the converter.
An oxygen sensor is no more good and should be replaced
The engine coolant temperature sensor is not working properly (change it first and see if code comes back)
Damaged exhaust manifold / catalytic converter / exhaust pipe (visually check over, if this and the first 3 come up negative change the converter.
Dec 28, 2007 at 9:56 AM
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