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Electronic Throttle Control System Test

  1. Connect a tachometer to engine. Warm engine to normal operating temperature. Depress accelerator, and release it. Engine speed should not immediately return to idle. On vehicles equipped with A/C, a slight increase in idle speed should be observed while A/C is turned on.
  2. Turning off A/C will return idle speed to normal. As the A/C clutch cycles on and off, the throttle kicker solenoid plunger should extend and retract. If plunger does not move with clutch cycling, or after engine starts, check the kicker system for vacuum leaks. If engine speed does not increase as specified, disconnect the 6-pin connector at carburetor.
  3. Connect ohmmeter leads from ground to solenoid terminal that was connected to Black wire. Resistance should be 20-100 ohms. If not, replace solenoid. Reconnect solenoid. Start vehicle and immediately measure voltage across vacuum solenoid terminals (before 2 second time delay times out).
  4. Voltage should be within 2 volts of charging system voltage. If not, replace computer. Turn on A/C after time delay has timed out. Charging voltage should once again be present at solenoid. If not, check wiring back to instrument panel.
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