long story short i just got my car back together awhile back and some problems i was having sounded like the tps. i checked the voltage and it was out of spec and i could not get it back into spec. i ordered a new one and could not get it in spec as well so i thought maybe they sent a bad one and now im on my 3rd tps and its still out so im thinking there is something else going on here. with the best of the 3 tps's i can get 3 of the 4 voltages in spec but one will always be out by about .5 volts.

any thoughts on what could cause this?

thanks

 

After 3 "good" ones i'd have to guess you were reading it wrong. If you confuse the 2 wires your readings will be about .5 off. Are you checking with a voltmeter or your PFC commander?

 

i dont think im reading them wrong ive been using the factory service and instructions from on here. im running the pettit ecu so im checking the voltage at the tps sensor.

2nd from top wire should read
.75-1.25v closed 4.8-5.0 open
bottom wire
.1-.7 closed 4.2-4.6 open

the best numbers ive can get is:
top wire
1.68 closed(out of spec) 4.8 open
bottom wire
.45 closed and 4.2 open

the top wire closed position and the bottom wire open voltage follow each other i can get one in but then the other will be out. the other 2 voltages stay in spec no matter what i do.

 

Rather than adjusting the TPS position, try first adjusting the throttle stop screw for more closure, then compensating for the idle speed change with the air bypass screw, then going back to adjusting the TPS position.

 

i read that some people adjust the tps with the throttle screw backed out so that the throttle is all the way closed and and the air bypass screw closed as well. that is the method im using.

i dont think it makes a difference but i just did a full non seq. conversion and removed the coolant line going to the throttle body and removed the thermowax
got rid of the rats nest/clipped off the unused solenoid plugs and soldered their ground wires together since it looked like the grounds were all looping to each other i know that the fpr solenoid is in series with them.