Engine coolant temperature compensation inspection

WARNING: This page is about a different car, the 2005 Mazda RX-8. However, it is still accessible from the selected car via links, so may be relevant.

Connect the WDS or equivalent to the DLC-2.
Select the following PIDs:
- ECT
- IAT
- RPM
Verify that the engine is cold, then start the engine.
Verify that the engine speed decreases as the engine warms up.
- If the engine speed does not decrease or decreases slowly, inspect the following:
  - ECT sensor and related wiring harness
    (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION .)
  - Throttle body and related wiring harness
    (See THROTTLE BODY INSPECTION .)