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Throttle Switch - Full Throttle Test

  1. Disconnect left fuel injection and EZF ignition control units. Connect ohmmeter to terminal No. 17 of EZF ignition control unit connector and ground. With throttle switch in idle position, ohmmeter reading must be infinity.
  2. With throttle 2/3 open, ohmmeter reading must be 0-10 ohms. If readings are incorrect, check readings directly on throttle switch. See Fig 1. Full throttle contact retards ignition timing by about 20 degrees.
  3. Ignition timing should about 40 degrees BTDC at 4000 RPM with throttle switch connector disconnected. Ignition timing should be about 20 degrees BTDC at 4000 RPM with full throttle contact connector jumpered.
Fig 1: Throttle Switch Connector
G34287