System Check
WARNING: This page is about a different car, the 2003 Mazda Protege5, 2003 Mazda Protege, 2003 Mazda MX-5 Miata, 2003 Mazda MPV, and 2003 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
- Ensure engine is at ambient temperature. Connect scan tool to DLC-2. Using PID/DATA MONITOR AND RECORD function, select ECT and RPM PIDs. Start engine.
- Engine speed should decrease as engine reaches operating temperature. If engine speed does not decrease or decreases slowly, check ECT sensor, IAC valve and related wiring.