How to wire an analog TPS to MS in a '90-'93 car.
#25
Boost Czar
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interesting.
but i dunno what the deal is with your wiring. You can check it the old fashion way to make sure you have the proper singals. The MSPNP2 docs say that's all you need to do for the tps: wire it in.
but i dunno what the deal is with your wiring. You can check it the old fashion way to make sure you have the proper singals. The MSPNP2 docs say that's all you need to do for the tps: wire it in.
The easiest way to check a TPS is to unplug it and put an ohmmeter on its pins. Observe the resistance as the throttle opens and closes. Each pair of pins will behave differently:
The resistance between the VREF 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 VREF and signal pins will be high with the throttle closed and low with the throttle wide open.
The resistance between the VREF 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 VREF and signal pins will be high with the throttle closed and low with the throttle wide open.
#28
Cpt. Slow
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Back from the dead!
I've been struggling with the TPS signal on Oregonmon's VVT swapped 1990. After following the VVT swap thread's instructions:
https://www.miataturbo.net/engine-pe...athread-80469/
I found the TPS wiring instructions for a 1.6 lacking. So I googled "90-93 miata vtps wiring", and this thread was the first non-m.net result. Followed these instructions to the T, as I was using an NB TPS:
But later on Braineack's instructions say that the 5v ref and signal are swapped from Joe's description
Even later still, Braineack confirms this wiring:
My original wiring was complete junk, resulting in random close throttle values from -10%-10%, and barely touching the throttle would result in it going upwards of 25% negative, before finally going positive around 50% throttle. Obviously this made closed loop idle and accel enrichments nearly impossible to tune.
If you're having these same issues, try following Braineack's wiring, it's correct, Joe (for possibly the first time every) is wrong.
I've been struggling with the TPS signal on Oregonmon's VVT swapped 1990. After following the VVT swap thread's instructions:
https://www.miataturbo.net/engine-pe...athread-80469/
I found the TPS wiring instructions for a 1.6 lacking. So I googled "90-93 miata vtps wiring", and this thread was the first non-m.net result. Followed these instructions to the T, as I was using an NB TPS:
If you're having these same issues, try following Braineack's wiring, it's correct, Joe (for possibly the first time every) is wrong.
#36
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Since this thread is back from the dead - I'll tack on a question I've been chasing. I just switched to a 4-Wire Auto TPS on my 1.6 and followed the wiring diagrams you all so graciously put out there for us! However, I have voltage creep on the sensor now. It will bottom out when I come off the throttle, and that is where I calibrated my TPS lower limit. However, if I let it sit there for a few minutes, it's voltage creeps up and the % showing in the TPS will creep up as well. After about 5 minutes it will be as high as 35 or 40%. Any ideas on how to diagnose/fix?
FWIW: I had it on a bosch variable TPS without this issue, but that throttle body exploded at the track so I swapped in the whole assembly from an auto car. 1.6 racecar.
FWIW: I had it on a bosch variable TPS without this issue, but that throttle body exploded at the track so I swapped in the whole assembly from an auto car. 1.6 racecar.
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Zaphod
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10-26-2018 11:00 PM