HU12 - Check Idle Control Pressure

- Transmission still in Park.

- A/C, heater and all accessories off.

- Engine at normal operating temperature and cooling fan Off, but not unplugged.

WARNING: DO NOT UNPLUG COOLING FAN. IT MAY CAUSE ENGINE OVERHEATING.

- Key On, Engine Running.

- Goose throttle and let it return to the idle position.

- Does the engine stall or does the RPM fluctuate excessively before returning to the idle speed specified in HU11?

YES -- GO to HU13. HU13 - Check IAC Solenoid For Proper Function

NO -- Air Intake system is OK. DISCONNECT Scan Tool. RETURN to Symptom Flowcharts to check other possible causes of the drive symptoms. Testing and Inspection