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Throttle Switch - Idle Contact Test

  1. Disconnect left fuel injection and EZF ignition control units. Connect ohmmeter to terminal No. 4 of EZF ignition control unit connector and ground. With throttle closed, ohmmeter reading must be 0-10 ohms.
  2. With throttle open, ohmmeter reading must be infinity. Throttle switch idle contact must open within one degree of throttle gap. Opening idle contact advances ignition timing by about 10 degrees.
  3. If ignition timing at idle speed is about 20 degrees BTDC, check for open circuit or defective throttle switch idle contact.