How to Adjust a TP Sensor on a Jeep Wranglerby Christian Killian
Adjusting the throttle position (TP or TPS) sensor on your Jeep Wrangler should only be done if the Jeep is running rough or starting hard and you suspect the sensor has been moved, or you are replacing the sensor with a new one. The sensor works on a system of input and output voltages that tell the Jeep's computer where the throttle blades are at all times. An improperly adjusted TPS will cause the Jeep to run poorly because the computer cannot properly compensate for the air and fuel being fed into the engine.
Turn the ignition switch in the Jeep to the "On" position but do not start the engine. Locate the connector on the back of the throttle position sensor but do not unplug it.
Locate the markings on the connector that indicate the positions. Each is marked with a letter starting with A and running through D. Insert the black test lead from your voltmeter into the back of terminal D, being careful not to damage the wire or terminal.
Insert the red test lead from your voltmeter into the back of terminal A. Note the reading on the voltmeter: this is the input voltage. Make sure that the throttle plate is completely closed when you take this reading.
Remove the red test lead from terminal A and insert it into the back of terminal B. Note the reading on your voltmeter: this is the output voltage of your TPS.
Divide the output voltage reading by the input voltage reading. The result should be between .825 and .835 (.830 is optimum). If yours is not in this range, adjust the TPS by loosening the Torx head retaining screws and turning the TPS slightly then repeat the test until it falls into this range.
Test-run the engine and drive the Jeep to make sure the TPS is functioning properly.
- When making adjustments to the TPS, loosen the top retaining bolt for small adjustments, and loosen the bottom retaining bolt for large adjustments.
Things You'll Need
- Digital voltmeter
- Torx screwdriver set
Christian Killian has been a freelance journalist/photojournalist since 2006. After many years of working in auto parts and service positions, Killian decided to move into journalism full-time. He has been published in "1st Responder News" as well as in other trade magazines and newspapers in the last few years.