So i have been having issues with this one since i bought it. It keeps throwing a code for the TPS and i put a new one in and upon testing the voltage to set the TPS i found something weird. I noticed That when i had my multi meter on the middle wire of the TPS wires coming from the harness with the red on the wire and black on a sanded piece of the body, that the car idles fine when i ground that wire... and when i take the cathode off of the body where i grounded it, it goes back to idling spastic and dying/or back firing... should i splice in a new throttle position connector? or is there something more I'm missing?? i sanded and cleaned every ground i found on the car after that to see but it didn't make a difference... plugs wires distributor cap and rotor are new as well as the battery cables... Ive been stumped on it all weekend i want to take the car to a car show for the 4th of july this weekend because the body and everything is clean but it just never ran right from when i bought it... Its got an LU5 motor, So i already checked and fixed vacuum leaks, I did not replace the fuel pump yet, but injectors are clean when i "ground" that TPS wire i can see them spraying fine, No exhaust leaks, Ive really went through some of the major problems with this bastard thing running... Help!lol

 

Where does that middle wire go to? Trace it and find where it's open or corroded.

 

Its the wire highlighted in the picture... it goes into the harness ill have to do some digging. its really been giving me hell!