I'm working on a dual throttle body setup on my car (supercharged). Since I needed to add the TB back onto the Intake I decided to get an NB TB so I can continue to use the NB IACV. I have a used OE TPS installed. At first it was not really calibrating at all but more research showed I was wiring it wrong. Now in Tuner Studio it will calibrate now but after several pumps of the pedal the % at no throttle will drift upward to 2-3%. What's an exceptable amount of % drift and are there ways to mitigate it?

 

You have your wire colors correct for their function on your original (I'm guessing '94?) harness. Mazda, according to the ProDemand wiring diagram I'm looking at, don't label their TPS connector 1-2-3, instead A-B-C, and they have A as the 5v ref, B as ground, and C as signal. So if we assume 1-2-3=a-b-c, you have signal and 5v reversed.

DIYautotune has a really good description of how a TPS works in their instructions, I think for adding a TPS to a 90-93, I've used this for wiring TPSs in other cars, most of them work the same.

• The resistance between the 5 volt and ground pins will remain constant.
  
• The resistance between the ground and signal pins will be low with the throttle closed and high with the throttle wide open.
  
• The resistance between the 5 volt and signal pins will be high with the throttle closed and low with the throttle wide open.
  

 

I verified this morning with a meter and you are correct, I had these 2 pins flipped. Working perfectly now. Thank you...