throttle position sensor

[dunmar]

Why does my throttle position sensor reading low voltage? I just replaced it two weeks ago.

[sracing]

Originally Posted by dunmar

Why does my throttle position sensor reading low voltage? I just replaced it two weeks ago.

??? The TPS doesn''t develop any voltage. It is just a potentiometer. Your ECM sends 5 Volts to it. (usually) One side of the TPS has this 5 Volts on it. The other side goes to signal ground (0 volts). The middle is the TPS voltage. It should go from ~0 volts to ~5 volts as you move the throttle.

So does it read low at closed throttle or full throttle?

Jim
SR Racing

[sierrap615]

year/model/make?

or is this a code? was the code cleared after replacement? do you have a multimeter.

[dunmar]

Originally Posted by sierrap615

year/model/make?

or is this a code? was the code cleared after replacement? do you have a multimeter.

The code was cleared after the new one was put in.
It is a 1991 Pontiac Grand Am.

[sierrap615]

a poor connection or a bad wire is possible, the new TPS may be bad but not likey.

[383PhoenixAm]

Well, depending on the application it could be calibrated wrong. I know on some cars the sensor will have too high or low a voltage if it is not set at a constant 5.14v (I believe) closed.