Save time and money on diagnostics by learning how to test a throttle position sensor on a Pontiac Fiero. The throttle position sensor, or TPS, is an important part of the car’s engine management, measuring how much throttle is being given, delivering optimal performance and fuel economy. With time and age, this part of your Pontiac Fiero tends to fall out of calibration or fail completely, requiring either readjustment or a complete replacement.
To test a throttle position sensor on a Pontiac Fiero, you will need:
- A screwdriver
- A set of ratchets
- A voltmeter
- Locating the throttle position sensor. The TPS on a Pontiac Fiero is located on the throttle body. In order to reach it, remove the air filter and the hose that leads to the throttle body. Note that some Pontiac Fiero engines may have a non-adjustable TPS installed on the throttle body, requiring that the entire unit be replaced in the event of failure.
- Testing the sensor. The connector leading to the TPS will have three wires. First, connect the voltmeter’s red lead to the dark blue wire carrying the sensor signal and ground the black lead, and then turn the ignition to the on position. You should get a reading of less than 1v. If it reads above 1v, the throttle position sensor requires adjustment.
- Adjust the TPS. If the TPS is not of the non-adjustable type, you can adjust the sensor by loosening the screws holding the TPS in place and rotating it until a reading of .5v appears on the voltmeter. When the correct voltage is obtained, carefully re-tighten the screws and reassemble the air filter and hose. If the correct voltage cannot be obtained, the TPS on your Pontiac Fiero may need to be replaced.