Idle Speed/Throttle Actuator - Electronic: Testing and Inspection

ON-VEHICLE INSPECTION
1. INSPECT IAC VALVE OPERATION
- Initial conditions:
- Engine at normal operating temperature
- Idle speed check correctly
- Transmission in neutral position
- A/C switch OFF



- Using a jumper wire (or SST 09843-18020), connect terminals TE1 and E1 of the DLC1.
- After engine speed is kept at approx. 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 ECM.
- Remove the jumper from the DLC1.

2. INSPECT IAC VALVE RESISTANCE

NOTICE: Cold and "Hot" in the following sentences express the temperature. of the coils themselves.
"Cold" is from -10°C (14°F) to 50°C (122°F).
"Hot" is from 50°C (122°F) to 100°C (212°F).

- Disconnect the IAC valve connector.



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

Resistance:
Cold: 17.0 - 24.5 Ohms
Hot: 21.5 - 28.5 Ohms

- If resistance is not as specified, replace the IAC valve.
- Reconnect the IAC valve connector.

3. INSPECT AIR ASSIST SYSTEM
- Initial conditions:
- Engine at normal operating temperature
- Idle speed check correctly
- Transmission in neutral position
- A/C switch OFF



- Using a jumper wire (or SST 09843-18020), connect terminals TE1 and E1 of the DLC1.
SST 09843-18020
- After engine speed is kept at 900 - 1,300 rpm for 10 seconds, check that it returns to idle speed.
- Stop the engine.



- Disconnect the air assist hose from the air pipe, and block off the IAC valve exit and the entry to the pipe.
- 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.
- Remove the jumper from the DLC1.
- Reconnect the air assist hose to the air pipe.


OFF-VEHICLE INSPECTION



1. REMOVE THROTTLE BODY
- Refer to Throttle Body Service and Repair.
Throttle Body

2. REMOVE IAC VALVE



- Remove the 4 screws, IAC valve and gasket.
INSTALLATION HINT: Place a new gasket on the throttle body.

3. INSPECT IAC VALVE OPERATION



- Connect the positive (+) lead from the battery to terminal +B and negative (-) lead to terminal RSC, and check that the valve is closed.




- Connect the positive (+) lead from the battery to terminal +B and negative (-) lead to terminal RSO, and check that the valve is open.
- If operation is not as specified, replace the IAC valve.

INSTALLATION HINT: Installation is in the reverse order of removal.