With the no start issue I have, I went and tested the voltage at the TPS. The best adjustment I can get out of my TPS, (end of slots) is 1.8 V at idle and 3.8 V at WOT using my dmm, blk on terminal A and red on terminal B. Does this fall in the range of operational ?

Doing the process of elimination of troubleshooting my no start issue.

 

Engine off / key on is the TPS .54 +- .07 ?

I've heard if they are set too high .63 or above it can enable the "anti flood" at cranking (like holding the gas peda) and not run the fuel pump ... I'm new to TPI setups though so Im just spitballing

~DaVe

 

Yes Dave, when the key is in the on position, I get 1.8 volts. The lowest I can adjust it to. I've read on this site the same, but only on the high side of WOT....anything above 6.0 V the ECM goes into "anti flood" mode.

 

Remove the tps from the throttle body and swing the lever through it's full range. Use your DMM to read the voltage as you did before. The tps is a simple potentiometer that has a finite resistance and outputs a voltage in reference to the wiper position in relation to ground and the supply voltage. The ECM provides 5 volts through the tps to ground, this is the range that should be seen at the wiper. The voltage at the wiper is what the ECM uses to determine throttle opening. If you have more than 5 volts at the wiper then the tps is probably bad. Anyway, you should be down around the 0.6 volt range with the throttle closed or the wiper at the ground end of the tps. You need to figure out why it is reading 1.8 volts at closed throttle position. HTH!

 

An operational tps should be .56 at closed throttle and over 4.2 at WOT with just the key on.

 

Agree...Hoping this is my cause for a no start...I'm going to take Bigal55 suggestion and remove the TPS from the throttle body and retake measurements. If I get .5-.6 volts with the lever closed, I'm going to try and elongate the slots in the plastic housing more to achieve these measurements with the TPS installed.

Thanks for everyone's input