High Idle After Warm-Up

WARNING: This page is about a different car, the 1997 Mazda Millenia. However, it is still accessible from the selected car via links, so may be relevant.

Verify correct throttle body dashpot adjustment (if equipped).
Check bypass air control valve IAC valve operation.
Check air intake system for leaks or restriction.
Check throttle cable adjustment.
Check coolant temperature sensor resistance.
Check airflow meter for cracks. Verify correct airflow meter operation and resistance value.
Check ignition timing.