I just replaced my tps sensor and now get a code for low voltage input. the old one worked fine,but looked crummy. I, put the old one back and still get low volt code. what is the trick or pocedure for aligning those little fingers on the flat end of the shaft. i have tried mall kinds of things with no luck. cel goes on in 1 or 2 min. HELP
tony

 

From the handy-dandy Chilton's manual for the '87-'91 model years, the 5.0L procedure specifically -
1) Disconnect the wiring harness from the TPS.
**** CAUTION *** Never smoke when working around gasoline! Avoid all sources of sparks or ignition. Gasoline vapors are EXTREMELY volatile.
2) Matchmark the sensor and throttle body for installation reference.
3) Remove the 2 retaining screws and remove the TPS.
4) Install the TPS so that the wiring harness is parallel with the venturi bores, then, rotate the TPS clockwise to align the scribe marks.
**** Caution *** Slide the rotary tangs into position over the throttle shaft blade, then rotate the TPS CLOCKWISE ONLY to the installed position. FAILURE TO INSTALL THE TPS IN THIS MANNER WILL RESULT IN EXCESSIVE IDLE SPEEDS!
5) Tighten the retaining screws to 16 inch-lbs.
NOTE: When correctly installed, the TPS wiring harness should be pointing directly at the air bypass valve.
6) Connect the wiring.

 

sorry, i should have mentioned yr. and engine. it appears that you just pop it on and put in 2 screws. there are no adjustments i can see. tony

 

The truck TPS is usually non adjustable, unlike the TPS in the mustang. A dremel is your friend here as you'll most likely need to elongate the mounting holes on sensor itself. There is a technical write-up in this forum on how to adjust the TPS to the proper voltage.

 

Did you disconnect the battery before replacing it? If not, the computer usually won't recognize you changed it.

 

what i did was take the tps off the truck and drilled the holes a little bigger so you could adjust it to the correct voltage, mine is at .97 volts. I have heard thats a good place to have it. here is a write up for you.

Take TPS off
Drill the top and bottom holes a little bigger
Put TPS back on
Turn Key On
Hook up multimeter, red lead to the green wire and the black lead to a ground, i just use my throttle body and that works
Check the voltage, then slightly rotate it
Mine was reading at about .81 so i slightly rotated it towards the engine till i found .97, then tightened it down.

 

The max you should go is .99, .97 is a good general adjustment.

 

ok i'll give that a try wed. just to be sure, plus lead of meter togreen lead of plug. neg. lead of meter to a good ground. slightly rotate the tps and shoot for about 9.7 vdc and tighten screws. there is not too much room for elongation of holes. how much did you elongate them and did you do both sides of the holes? thanks tony

 

on mine i just had to drill the metal plugs out in the holes and that was enough, just do both holes. once i did that just had to rotate it towards the block slightly and got it at .97 then tightened the screws down. just remember .97 or higher, just less than 1.0 volts.

 

just a couple more?'s. I have no green wire looking at the 3 wires when plugged in from top to bottom are.
brown-white stripe, grey-white stripe, grey- red stripe. is this done with ign. on and engine not running? do i just start at top wire and work down since i don't have a green wire and i am assuming you used a needle sharp probe to punctute the wires or stick in the end connector.
your help is greatly appreciated by the way. tony