Throttle Position Sensor: Testing and Inspection

Description:

PROCEDURE
Using a Digital Multimeter (J 39200 or equivalent) perform the following steps:
1. Insert a 3.5 mm (0.14-inch) feeler gage between the throttle stop screw and the throttle lever.
2. Inspect the Idle Speed Control (ISC) motor plunger. If the ISC motor plunger is contacting the throttle lever screw, then the engine must be brought to operating temperature.
3. Back probe the TP sensor signal circuit at the PCM connector to ground.
4. Turn ON the ignition.
5. Observe the TP sensor voltage on the DMM. If the TP sensor voltage reading is not 0.98 to 1.02 volts. adjust or replace the TP sensor. Refer to appropriate procedures in this section.

Using a scan tool perform the following steps:
1. Insert a 3.5 mm (0.14-inch) feeler gage between the throttle stop screw and the throttle lever.
2. Inspect the Idle Speed Control (ISC) motor plunger. If the ISC motor plunger is contacting the throttle lever screw, then the engine must be brought to operating temperature.
3. Connect a scan tool to the Data Link Connector (DLC) and select the TP sensor voltage parameter.
4. Turn ON the ignition.
5. Observe the TP sensor voltage on the scan tool. If the TP sensor voltage reading is not 0.98 to 1.02 volts, adjust or replace the TP sensor.