Intake Air Control Valve (IACV) System: Non-Turbo
- Check for loose or leaking vacuum connections. If vacuum connections are okay, disconnect vacuum hose from actuator valve. Connect vacuum pump to actuator valve. See Fig 1.
- Apply 16 in. Hg of vacuum on actuator valve, and ensure actuator rod pulls inward and air valve fully closes. If air valve does not fully close, it may be necessary to rotate adjusting screw until air valve fully closes. If air valve fully closes, remove vacuum pump, reconnect vacuum hose and proceed to step 3). Replace actuator valve if actuator rod does not pull inward.
- Disconnect vacuum hoses from vacuum tank. The vacuum hose from actuator valve will lead to the vacuum tank. Apply air pressure to port "B" on vacuum tank and ensure air passes out port "A". See Fig 2. Apply air pressure to port "A" and ensure air does not pass out port "B". See Fig 2.
- Plug port "A" on vacuum tank. Using vacuum pump, apply approximately 20 in. Hg of vacuum to port "A". See Fig 2. Ensure vacuum reading will hold for at least one minute. Replace vacuum tank if defective and recheck system operation. If vacuum tank is okay, reconnect vacuum hoses and proceed to step 5).
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Disconnect electrical connectors from IACV Vacuum Switching Valve (VSV). The VSV contains a 2-wire connector with a Light Green/Black and Black/Red wires.
- Apply air pressure to port "B" and ensure air passes out the filter. See Figure. Connect battery voltage to VSV terminals. Apply air pressure to port "B" and ensure air passes out port "A". See Figure.
- If IACV VSV is okay, check wiring circuit. See appropriate wiring diagram in WIRING DIAGRAMS
article in the ENGINE PERFORMANCE Section. The Electronic Control Unit (ECU) controls the IACV VSV ground circuit on the Light Green/Black wire. The ECU is located above the glove box.