Unstable TPS reading after BP swap
 

Here is a rundown of the previous setup and what I am running currently. Basically went from a 1.6 with a BMW TPS to a BP05 engine using a 99 IM and Throttle Body, I am running a MS3ProPNP for a NA 1.6, cam sensor installed in back of exhaust cam, rewired for sequential injection. I soldered all wires properly and do get variable reading from the TPS. However the TPS is never stable at closed position. I changed the TPS since the IM came off a parts car that sat in my yard for a while and I figured that might be bad. I never had an issue before with the BMW sensor. I see anywhere from 830-860 counts at closed position for the TPS. Sometimes it reads negative as much as 15% and other times at idle it will show 6-10%

Also it seems that if I am in the gas about 5% throttle, then it reads high in TunerStudio. I checked the throttle cable and it has slack, isnt holding the throttle open either. I am still trying to square away idle with the new NB IAC but overall it runs ok. Could it be a bad throttle body or too loose of a spring? Here is a copy of my tune and some logs of a drive home. I literally got this thing running a few days ago so I havent had time to really mess with the tables too much so dont bash too hard lol.

That's gotta be a compromised signal ground circuit. Really no other explanation for why or how CLT and MAT sensors with very low bandwidth move that fast, especially so tied to RPM/Duty as yours are.

If you are running frankenstein 1.6/1.8 wiring this might help you, fixed all the noise on all ADCs for my old 1.6, made it run so much better.

https://www.miataturbo.net/build-thr...7/#post1354392

Thanks I will check that out. Did you just run it to a different ground location?

No, just cut it.

Figured it out. I had to swap the outer pins on the TPS sensor connector. Once I did that my closed counts were about 100-105 and WOT was 700-725.