Throttle Position Sensor: Testing and Inspection

Throttle Position Sensor (TPS) Location:

To test the Throttle Position Sensor, located on the carburetor, proceed as follows.

Accelerator Cable Adjustment:

1. Loosen the accelerator cable.

Speed Adjustment Screw (SAS) Locations:

2. Sufficiently loosen the speed adjustment screws #1 (SAS 1) and #2 (SAS 2) to close the throttle valve completely.
NOTE: Turning the screw counter clockwise closes the valve. Record the number of turns to remove each screw (to speed reinstallation). At this time, the fast idle control should have been released (the lever not resting on the fast idle cam).

Connector C15:

3. Connect a voltmeter (digital type) between terminals 2 and 3 of the Throttle position Sensor (TPS) connector pins (terminal C15).
NOTE: DO NOT disconnect the TPS connector from the chassis harness. To test pins, insert a straight pin or needle from the back side of the connector to access the pin.

4. Turn the ignition switch to ON. (engine will not start)
5. Measure the TPS output voltage.
Standard value: 250 mV
6. If the output voltage is not correct refer to ADJUSTMENT PROCEDURES.