Throttle Opener Control System
- Disconnect electrical connector at throttle opener Vacuum Switching Valve (VSV), located in front of valve. The VSV contains a 2-pin connector with a Light Green/White and Light Green/Red wire.
- Turn ignition on. Using test light connected to ground, probe Light Green/Red wire at VSV connector. If test light comes on, proceed to step 3). If test light does not come on, check for open circuit in Light Green/Red wire between VSV and EFI main relay. The EFI main relay is mounted on ECM, located under left side of instrument panel, near kick panel. See Figure .
- With test light connected to battery voltage, probe Light Green/White wire of VSV electrical connector. If test light does not come on, proceed to step 4). If test light comes on, check for short to ground in Light Green wire between VSV and ECM. The ECM is located under left side of instrument panel, near kick panel. See Figure . If wiring is okay, replace ECM.
- With ignition off, remove vacuum hose from throttle opener port on VSV. Connect a hand-held vacuum pump to hose, and apply vacuum. If throttle opener does not move, check hose for leaks and kinks. If hose is okay, replace throttle opener. If throttle opener moves, proceed to step 5).
- Reconnect vacuum hose to VSV. Remove intake manifold-to-VSV vacuum hose at the intake manifold. Connect hand-held vacuum pump to hose, and apply vacuum. If throttle opener moves, proceed to step 6). If throttle opener does not move, check hose for leaks and kinks. If hose is okay, replace VSV.
- Turn ignition off. Using test light connected to ground, backprobe Light Green/White wire at ECM. Turn ignition on. Apply vacuum to hose disconnected from intake manifold. Note if throttle opener moves. If throttle opener moves, replace VSV. If throttle opener does not move, no problem exists in the system.