So, I've been searching & can't find the answer. I have a 1989 3.0 4runner giving me a "can't read TPS" code. So I go to the junk yard & am in luck, a '93 3.0 with the throttle body still attached so I pull the TPS.... they'll be the same, right? 3.0 <-> 3.0... get ready to switch & I see different part numbers??? I now know there was a P/N change but just need assurance that if I adjust it correctly the new one will work. Anyone else done this?
Original P/N - 89452-28030
"New" P/N - 89452-12040

 

the 93 will not work on the 89. Different part numbers means different parts.

 

besides Toyota changed a number of things in 92, including water passages, and timing belt tensioner. They also changed many things in wiring, etc etc. Toyotas wiring harnesses only interchange in an about 6 month period.

 

You can use the newer TPS if you change two other parts. First, you need to change the plug. The newer one has a rounded plug while the older one is squared. Secondly, (I don't know what one would call this part) you must change the metal part on the throttle body that actually moves the TPS. The reason this needs to be changed is that the newer TPS internals are clocked 90 degrees differently than the old one.

 

You can test the TPS you have, it may just be out of adjustment:
- http://www.4crawler.com/4x4/CheapTricks/TPS/index.shtml

Or it could be a wiring issue between the TPS and ECU.

 

Some of the TPS sensors and connectors had a different number of terminals, also. I've seen that before....not sure what years, though.

You can test the terminals at the ECU end of the TPS for continuity. It's really very simple.....if you have an ohm meter, I suppose. Look under "testing the ECM wiring resistance" (EG2-256)in the FSM.
http://personal.utulsa.edu/~nathan-b...e/102engin.pdf

And just a tip, it'd be so much easier on you if you used a TPS for your year model.