TPS problem!

[Scott_B]

Been having idle problems. Works good, other times wants to die. Anyways, i tried to check the TPS. Went black to ground, Red to the Green wire. Im getting a reding of 4.97. WTF is up with that? i tried to adjust it, but can only get 4.96 or so.

I tried anothe TS i has laying around, same result..also tried multiple grounds, same thing. Im pretty sure i have my meter set right. tested my battery, got 12v. Doing the test with the key on, car off. what am i doing wrong? If i sweep the throttle, it goes up to 5.01.

Help guys!

 

[jrichker]

Use the black/white wire for ground, the dark green/green wire for TPS signal. Use only these two wires to set the TPS base voltage.

The orange/white wire is VREF, which is supposed to be 5 volts +/- .25 volt.

Remember that when you turn the idle set screw, you change the TPS voltage.

With the power off, measure the resistance between the black wire and battery ground. You should see less than 1 ohm. Check the same black wire on the EGR and MAP sensor. More than 1 ohm there and the wire is probably broken in the harness between the engine and the computer. The 10 pin connectors pass the black wire back to the computer, and can cause problems.

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif