Without using WDS or equivalent
WARNING: This page is about a different car, the 2004 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.
- Inspect the following:
- EGR pipe clogging
- PCM terminal voltage
- EGR valve signal
- Vehicle speed signal
- Throttle opening signal
- Engine coolant temperature signal
- EGR valve (If it is stuck or not moving smoothly, replace it with a new one.)