Gil BullyKatz said:
I did this a few minutes ago and the ground wire at the tps square connector is reading 0.68!
I am at a loss when it comes to electrical issues so please explain "ground fault"...
Can I run a chassis ground wire and splice it in to fix it?
Or do I have to spend hours chasing down wire connectors?
Either Pin D to Pin D on the 2 square conectors are not making good contact (thus we call it a "ground fault", as the connection is faulty, and the ground has resistance through the bad contact at the connectors (pin D male to pin D female on the square connector), or the other end of the wire from Pin D is loose, corroded and dirty, or the worst case the wire is broken inside the pvc insulation and good luck finding it, in which case just splice a new ground wire in at pin D near the wiring harness connector on the wiring harness side of the connector to the TPS sensor.
Also you need to clean and tighten all the ground connections:
1) The battery negative terminal and the wires and connectors there.
2) The flat terminal ends of the multiple wires running the the engine block near the oil dip stick.
3) Both ends of the ground strap on the drives side, top of the engine block head in the rear to the firewall.
The OEM ground strap (#3) is a silver colored Stainless steel wire mesh flat cable. Be sure to use sand paper or scotch brite to remove corrosion from the flat terminal connectors on all the flat washer like contact ends and also clean the cast iron block surface and firewall surface with the abrasive. Not much you can do with the square connector except use very tiny needle nose pliers to close the gap and tighten the female connector so it is tighter when reassembled.
One of those three ot the TPS/wiring harness Pin D connection is probably the where the bad connection is causing the extra ground resistance.
From the data you posted, the problem is not the 5 volt signal, the problem is a poor ground connection. Your old TCU and TPS may be good! Save them and test them once you have fixed the bad ground before tossing them (if you still have them).
Oh, and by the way, the ground problem can come and go on its own as the engine block and wire connectors get hot, cold and shift around as the engine moves!!! That is why it tested OK before and is testing bad now! I fought that problem for a while too.
I fixed all four of the above problems on mine just to fix a fast idle on the 3 pin, ECU side of my TPS, and then had to run a new ground wire for Pin D on the TCU side of my TPS to solve the transmission sifting problems.
Good grounds are essential!!!!
One last thing, Mud8 was telling you to run those tests he suggested earlier with the TPS connector
disconnected and
power turned off. Then you switch from volts to ohms on the meter (may need to move the probes to a different pin location and set, turn the dial to ohms, varies with different meters), then test fron pin D to a know good ground, namely the negative terminal of the battery. If it reads more than 1 ohm then the ground wire is bad or the connection on the other end of that ground wire is loose, dirty, etc. 5-90 gave you a way to run that same ground test with the power on using volts scale.
From what you have said, I would clean all those grounds first, retest Pin D to ground, and then if needed (If it is still higher than 1 ohm from pin D to ground of the power off, disconnected square connector on the wiring harness side, to the negative battery ground terminal, then I would run a new ground wire from that side of the TPS sensor as described above to the negative battery terminal or to the firewall ground bolt (SS flat strap)
and the search feature!
