Possible Causes
WARNING: This page is about a different car, the 2003 Mazda Tribute. However, it is still accessible from the selected car via links, so may be relevant.
Possible causes are:
- Damaged catalytic converter.
- Damaged exhaust manifold.
- Damaged exhaust system pipe.
- Damaged HO2S.
- Damaged muffler/tailpipe assembly.
- Downstream HO2S wires improperly connected.
- Engine misfire.
- Fuel pressure too high.
- Malfunctioning ECT/CHT sensor.
- Oil contamination.
- Retarded spark timing.
- Using leaded fuel.