The Throttle Position Sensor (TPS) output signal is an important input for both the engine and transaxle control modules. A malfunctioning TPS may result in the following symptoms:
Uneven throttle response;
Slip and shock during the 1-2 and 2-3 shift on Automatic Transaxle (ATM)-equipped vehicles;
Erratic ATM shifts with possible shift flare (engine RPM increases during shifts);
Check that the engine light is on (light may go off, but the code will remain stored); and
TPS-related code stored in the ECM and/or TCM.
1996-2000 Elantra; and
1. Check to see if the following three conditions are met:
The TPS is suspected;
The ECM/TCM has no codes stored; and
The TPS has the words “DAE SUNG” molded on the part.
If so, conduct the following diagnostic procedure:
The vehicle must be idling (with all accessories turned off).
Push on the side of the TPS connector toward the dash panel. The force used should be firm enough to slightly deflect the TPS housing, but not enough to damage or break anything.
If the TPS is not operating properly, the engine will surge in response to your push.
If the Hi-Scan Pro or HDS is used to record the TPS output, the above procedure will show that the TPS output increases toward 5V when the connector is pushed.
2. If the ECM has a TPS-related code stored (with or without the MIL on), replace the TPS.
Technical service bulletin courtesy of IDENTIFIX.
For additional tech tips, visit www.identifix.com.