I'll take your old one off your hands.

The way that the TPS works is simple. A VDC is supplied to the VC terminal (Red/Black wire) which is the positive side of the resistance strip. On the other end of the connecting strip is the E2 or nagative terminal (red wire) . The control arm connects to the resistance strip and crosses over to the signal strip connected to the VTA1 terminal (yellow wire). The VDC should be constant through the VC terminal and the E2 terminal. As the control arm gets closer to the VC terminal (positive) resistance decreases and the voltage signal increases. This is due to the contact signal strip recieving a cleaner resistance voltage, than lets say farther away near idle. If the resistance strip has defects and the contact control arm does not pass on proper voltage signal, the ECU does not know where exactly the throttle valve is located. This causes erratic idle, erratic power loss due to the ECU trying to compensate. The large defect found in my TPS was at the E2 ( negative) side of the resistor strip. The copper has warn away. This is strange becouse there are no moving parts at this location. I have to assume it is due to heat damage caused from the resistor itself. The same thing has been found at the signal terminal and the positive terminal sections of the strip. The design has a small copper prong set into the resistor strip material. Not a bad idea if the conductive material actually didn't disintigrate. Also if you look at the plastic part that actually connects to the mechanical shaft of the throttle valve. You will notice either soot buildup or impressions in the plastic where the shaft end connects. These little discrepancies are enough to throw off the voltage signal reading to cause a notice in performance. An easy fix for this is to use RTV. Fill the end piece with RTV and then install. This will keep the soot out and create an extra secure fit to eliminate that little wiggle which causes warping of the plastic.

 

Yeah. I still don't know if the tps is bad. I had tested the values many times and never found any problems with it. But my idle jumps all over the place. I hate replacing parts if I can't verify they are bad. But this is one of those times I just have to finally bite the bullet and see. If it fixes my idle problem, I will be happy to mail you the bad one(assuming it's bad) for furthering your r&d. Otherwise, it will sit on the shelf next to the good, used MAF and ECT spares.

 

What was your voltage reading at the (positive) Red/black striped wire? What was the signal voltage of the yellow wire at idle and full throttle?

 

I don't remember. I think I posted it in a thread a while back(more than 4 months). I can take some readings another day when I have time, before I replace the TPS. I had checked the TPS when the idle was acting normal(700rpm), and at high idle(2200-3000rpm) and low idle(450rpm). It fluctuates a lot. And not gradually. I can drive along and have a base idle of 2500rpm when I stop, and the next time I stop the idle will be 450rpm. Tap the throttle a few times and it will eventually return to normal or to high idle. And the high idle is always changing. One time it will be a steady 2200, another time a steady 3000, next time 450, next time 2700, next time 700...so on and so forth. IACV, ECT and MAF already changed out with no change. ECM opened and inspected with zero corrosion and no bad components.

But enough about me...tell me about you....

 

If you look at this picture of my drawing of the resistor strip. You will see to the left is the negative terminal connected in continuity to the positive. The lower black shaded strip is for the signal voltage. This is where the ECU gets information. Look at the arrows. from left to right the voltage gradually increases within the range. The range is actually where the contact arm works to transfer the resistance voltage to the signal strip. But wait theres more. Look at the shaded line running up and down towards the right. This is the maximum voltage range within both strips. If your TPS is warn it can travel to this range and cause high RPM's. Also to the right of the maximum range the voltage decreases as you go farther right. If your control arm is traveling within this range, it will cause high RPM's and then gradually be reduced when you think you have the throttle to the floor. This is what you call the governor range. The material used inside these TPS's are soft plastic. They heat and flex. It is not unusual for the control arm to venture within these unwanted ranges. The center range is where the engine should be.

https://landroverforums.com/forum/me...y2420-2818.jpg

 

In this drawing you can see where I have figured out the actual mechanical range in comparison to the inner TPS control arm range. Both ranges consistantly mimic a 45 degree angle. This motion of range has to be duplicated in all accuracy when finding a universal replacement part. The voltage range is too easy, most TPS run the same values. However The range of the contact control arm must be exact with the motion range of the throttle valve. Most TPS are different in this manner. Probably for capitalizing purposes.

https://landroverforums.com/forum/me...y2419-2819.jpg

 

What about a hall effect sensor. We use them in some of our equipment...
Hall Effect Sensor Solutions - Rotary, Non-Contact :: BEI Sensors | Duncan

 

Granted, you lose the low cost parts if you do that.

 

Pretty sure I found a TPS that will bolt right up for $14.00. Still need to determine it's range though. However I can cast a plastic base and change the rotation to aquire the range needed if necessary.