On-Vehicle

INSPECTION

Idle Air Control (IAC) Valve Operation Inspection.

1. Verify initial conditions:
- Engine at normal operating temperature.
- Idle speed set correctly.
- Transmission in neutral position.
- A/C switch OFF.





2. Using jumper connect terminals TE1 and E1 of the Data Link Connector 1. (SST 09843-18020)
3. After engine speed is kept at approximately 1,000 rpm for 5 seconds check that it returns to idle speed. If the engine speed operation is not as specified check the IAC valve, wiring, and Engine Control Module (ECM).





4. Remove the SST from the Data Link Connector 1. (SST 09843-18020)

IAC Valve Resistance Inspection

1. Disconnect the IAC valve connector.





2. Using an ohmmeter measure the resistance between terminal +B and other terminals (RSC, RSO).

Resistance: 19.3 - 22.3 Ohms at 20°C (68°F)

If resistance is not as specified replace the IAC Valve.
3. Reconnect the IAC Valve connector.

Air Assist System Inspection

1. Verify initial conditions:

- Engine at normal operating temperature.
- Idle speed set correctly.
- Transmission in neutral position.
- A/C switch OFF.

Ignition Timing Connector:

2. Using jumper connect terminals TE1 and E1 of the Data Link Connector 1. (SST 09843-18020)

3. After engine speed is kept at 900 - 1,300 rpm for 10 seconds, check that it returns to idle speed.
4. Stop the engine.





5. Disconnect the air assist hose from the air pipe and block off the IAC Valve exit and the entry to the pipe.
6. Start the engine and check that the idle speed reaches 500 rpm or below (the engine may stall).
- If the idle does not reach 500 rpm or below, check for a leak between the air pipe and injector.





7. Remove the jumper from the Data Link Connector 1. (SST 09843-18020)
8. Reconnect the air assist hose to the air pipe.