NOTE: Throttle Position (TP) Sensor on gasoline engines is not adjustable. Replace TP sensor is not within specification.

Unplug PCM 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Repair as necessary. Connect Breakout Box (T83L-50-EEC-IV) and reconnect PCM to breakout box. Connect digital voltmeter positive lead to pin No. 47 and negative lead to pin No. 46. Turn ignition on. Observe voltmeter while moving throttle slowly to Wide Open Throttle (WOT) position. Release throttle slowly to closed position. Voltage should change smoothly from about .6 volt at idle position, to about 4.5 volts with throttle wide open.
If voltage is not as specified, ensure throttle stop screw and linkage are adjusted correctly. Remove TPS and check for damaged, corroded, or misadjusted pins. If pins are okay, install sensor. Ensure sensor is seated correctly. Repeat step 1). If voltage is not as specified, perform CIRCUIT TEST DH in TESTS W/CODES - EEC-IV article in the ENGINE PERFORMANCE section.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Throttle Position (TP) Sensor