Ok, so hopefully if someone else is going to do this internal mod they read far enough to see that I screwed up and mislabeled the original picture leading Brainack to give the wrong wiring instructions.





Here are the correct labels and wiring to work with the stock harness. This time I actually double checked the outputs with the multimeter and verified against the info Brainack quoted.

 

:P

 

This is awesome. Thank you!

 

My apologies for bringing this thread back from the dead, just curious if the OEM 90-93 engine harness TPS connector can be re-pinned to function correctly without the need to cut open the TPS and solder inside of it. I am thinking just swap wire position 1 and 2 and be done with it on the TPS connector.

Anyone know if this will work?
Thanks!

 

That's the way a normally sane person would do it. The reason I went through the trouble of rewiring it was so it was fully reversible every 2 years when I have to take it in and get it smogged.

Between this, the intercooler, bigger injectors, etc., the list of things to switch out every 2 years is getting longer!

 

Thanks!

Searching now to see if anyone has a how to for de-pinning that connector, not having much luck yet...

 

As much as I hate altering the OEM harness, I just cut and swapped the two wires in the harness. Bit of solder and shrink wrap and everything is happy.

 

^ No more invasive than depinning the connector and probably a lot faster and easier if you are going to permanently alter things.

 

As a follow up, I ended up trying for about two hours with jewelers screwdrivers to de-pin the TPS connector, couldn't get it to budge, I just cut 1 &2 and soldered them together and put on some shrink wrap tubing, wrapped in 3M electrical tape, plugged it in , for the base plate I used flat aluminum and a few small flat head washers stacked on top of each other to act as bushings between the TPS and the base plate, with a small bolt/lock washer and nut combination to hold it in place. works flawlessly.

Duralast Part Number TPS4185 - $53.99

It took about 30 minutes excluding the failed attempt at DE-pining the connector.

 

Sorry to bring this back from the dead but I wanted to mention I recently used a TPS4158 on my '91. I did the internal mod. Dremeled the top off and resoldered the pins to match the Miata harness and hot glued the top back on. I previously had a TPS201 and in my experience, this is significantly less noisy.
Wells TPS4185 internal mod

 

Bumping this, as either I am confused or something is screwy.

I have been tasked to make a 3d printed bracket for these, which I have done. I installed the assembly onto my 1.6 for testing purposes and did not have to rewire or modify the sensor.

Referencing the earlier pic in the thread that numbered the external pins to their internal connection, this is the schematic diagram of the TPS.

Its a weird pot. The dual element explains why the value across the "apparent" element can be less than the value of the wiper to either of the other pins.

The ground must be connected to either end of the element and cannot be connected to the wiper. You cannot make provisions for this at the ECU side because the ground connects somewhere in the harness to chassis and engine. So, as long as ground is on pin 1 or 2, nothing needs to be rewired, and literally any other combo can be made to work by wiring the ECU side accordingly.

My issue: my car(1990, unmolested to my knowledge) has the ground on the middle pin, #2. 1 then gets 5V from MS and 3 is TPS sig back to MS.

This is Ricks showing the black, which is one end of the element going to the middle pin, which has a 50/50 of being ground, because orange is the other end, and I suppose that could be ground which would still work with the KIA TPS without rewiring.


The OEM schematic shows the middle pin, #2, as ground (although theres no way it can work with the wiper grounded as shown(unless they are using some whacky circuit topology that ive never seen used(even though the 90-93 didn't have a wiper but only a switch, and none of this matters anyway, this is a run on sentence, so whatever)))


So why are we cracking these open and rewiring them? My car is running with the KIA and all I did was remove the TPS201 that i had, plugged in the KIA TPS and did the min value, max value thing in tunerstudio.

@shuiend

@Braineack

I will publish bracket STL soon

 

Correct, Middle pin is ground.

IIRC it's Idle Switch, Ground, WOT from top to bottom.

Traditionally, we've wired the connector 5v, ground, sig at the ECU. If ground can stay in the middle, and you just need to swap 1 and 3, then it can be done at the ECU harness and no mod to the TPS itself has to be made.

 

Yea you have two choices on ground, either end of the element, and since the factory harness lands on one of those, no need to open the TPS. I didn't think of the PNP type ECUs that don't utilize an adapter harness that allows you to customize where the wires go, but... I still think it'd be easier and cleaner to re-pin the TPS connector, or ECU connector than to modify the TPS itself. Also saves your warranty since we seem to kill a lot of TPSs on our cars.

https://www.thingiverse.com/thing:2425389

 

This has made me so happy! Now to get a friend with a 3D printer to print one.

Thank you, so very very much!

 

PM me if you need one printed.

 

Thanks for creating this. Printing one for sure.

 

Here are some crappy photos of it the TPS bracket printed and installed. I repinned the TPS connector. Thanks again for designing this.

 

Looks great. I have also printed a couple but have yet to install it as I try and figure out my Auto TPS issues. Which sensor are you using in the photo? What year/car is it from originally?

 

Its the Kia TPS, you can find the part number in the thingiverse link.

 

Ha, that's what I thought, but it just looks so OEM! <3