Q: What is the Throttle Position Sensor and how do you diagnose and replace it on Toyota Avalon and Toyota Solara?
A: Locate the Throttle Position Sensor (TPS) on the end of the throttle shaft to check it. Verify the reference voltage located on the Powertrain Control Module (PCM). Disconnect the TPS electrical connector and touch the probes of a volt meter to terminal number 1 and ground. With the ignition key turned ON, it should be 4.5 to 5.5 volts. If it is out of range or if there is no reference voltage, have the PCM checked. Next, check the TPS signal voltage. Reconnect the electrical connector to the TPS. Back pin terminals 2 and 3 of the TPS electrical connector. With the ignition key turned to ON and the throttle fully closed, the voltage should read 0.3 to 1.0 volts. Then, slowly open the throttle to increase it. If the indicated readings are below or above the specified range, replace the TPS. To remove it, make sure the ignition key is in the OFF position. Disconnect the electrical connector from the TPS. Remove the screws that retain the TPS to the throttle body and remove the TPS. Installation is the reverse of removal.