Possible Causes
WARNING: This page is about a different car, the 2002 Mazda B4000, 2002 Mazda B3000, and 2002 Mazda B2300. However, it is still accessible from the selected car via links, so may be relevant.
Possible causes are:
- Using leaded fuel.
- Oil contamination.
- Engine misfire.
- Damaged HO2S.
- Malfunctioning ECT sensor.
- Downstream HO2S wires improperly connected.
- Fuel pressure too high.
- Damaged exhaust system pipe.
- Damaged exhaust manifold.
- Damaged muffler/tailpipe assembly.
- Damaged catalytic converter.
- Retarded spark timing.