Possible Causes
WARNING: This page is about a different car, the 2003 Mazda B4000, 2003 Mazda B3000, and 2003 Mazda B2300. However, it is still accessible from the selected car via links, so may be relevant.
Possible causes are:
- Contaminated HO2S.
- Crossed HO2S signal wiring or signal return wiring.