upon messing around with my Tps sensor i realized that the ground for it is completely severed and when i try to attach the wires together again when the car is running, it runs like a crap sandwich and dies, but when ground isnt connected the car runs, but i have a fuel cut issue.

Any thoughts?

 

What is the year of the car? And what is the color of the wire?

 

Its an 87 S4 with an S5 engine swap. And the wires are spliced into just the narrow range of the TPS on the S5 throttlebody and the full isnt in use i believe off the top of my head. The car is getting fuel cut at random times and is making me want to pull my hair out..

The original S4 TPS clip black with red stripe is ground





The S5 clip spliced into the S4 The red with black stripe is the ground that was detached. When i touch the black with red to this one the car runs like garbage.. Bad TPS maybe?





The FSM the wires in my hand are A B and C which is the narrow range.

 

Just to clarify, you have Black/Red connected to Brown/Black?

 

Yes that is correct! well now theyre disconnected and the ground isnt attached to anything.

 

With all three wires connected and the engine as fully warmed as possible the G/R wire should read 1 volt w/key to on. What does yours read. Also, when the TPS is unplugged the ECU defaults to full throttle operation which might mask other problems w/the engine if it runs fine when unplugged. And are you using a USDM ECU?

The Brown/White wire ought to read close to 5 volts and the ground ought to read at 0 volts w/key to on regardless of the engine temp. And the voltage range of the G/R wire is 1 volt at idle and 4.5 volts with the TPS plunger fully extended (this sweep test can be done w/the engine not running, but key to on).

 

ok just checked and the green/red was at 5V and so was the solid brown(orange maybe)? and the gorund read 0 because its completely severed from the TPS. It is a USDM ECU btw. The guys that did the swap claimed they knew what they were doing and the car ran great for a while... until i started driving it more and more.




this is what were working with here. S5 clip is on the top and the S4 clip is on the bottom. The black and red wire on the bottom isnt connected to anything and both the grn/red and brown colored wire are reading 5V

 

The voltage test of the wires will be meaningless unless all of them are hooked up properly and this includes the ground wire. I mean just wire the wires to how they are supposed to be and go from there. If it means taking the ground wire from the TPS pigtail and wiring it to the emission harness before the plug then do so. If it means wiring it to another ground wire from another engine sensor, such as the pressure sensor etc, then do so. You should expect nothing good unless the three TPS wire are connected properly.

 

Ok so off the TPS side so the S5 clip which are the ground wires so i can just ground them out?

 

To make sure I actually understand what you are asking could you please specify what color plug and which wire color you are not sure of.