Idle Air Control (IAC) Valve, Checking

Idle Air Control (IAC) Valve, Checking

- Remove IAC valve -N71- from mounting on engine (do not disconnect harness connector).







- Visually inspect rotary valve for scuff marks (arrow).


CAUTION!
Do not use a screwdriver or other tools to check the valve for ease of movement.


- Initiate output Diagnostic Test Mode (DTM) and check actuation of IAC valve. Output Diagnostic Test Mode (DTM) (Function 03)
- Check that rotary slide moves freely between fully open and fully closed positions.

If there are scuff marks or other malfunctions that restrict free movement of rotary slide:
- Replace IAC valve.
- Check Diagnostic Trouble Code (DTC) memory.
- Generate readiness code. Readiness Code, Generating

If valve does not respond:
- Check idle air control signal from ECM. Refer to "Idle Air Control (IAC) Valve, Electrical Testing" Testing and Inspection

Idle Air Control (IAC) valve, electrical testing
- Check IAC valve -N71- mechanical function.
- Disconnect harness connector from valve.