ghia nut

Good evening.
I have used the search function so please be gentle, my body/mind is weary because this is kicking my ***.

I have a 1992 miata.
I am installing a beta version arduino based megasuirt pnp by speeduino.
It runs megasquirt etc etc. (corrected by shuiend it does not use megasquirt firmware and uses tuner studio as an interface, it does have its own firmware, my bad.)
I have installed a 4 wire vtps and throttle body from an automatic 1.6

I am having issues with vtps. At first I wired it according to Mr. Joe
The vtps signal on tuner studio would keep climbing from 16% up for 10 minutes up to 30% ish, but would show some changes. it would register 100% but never 0%
Then i wired it up this way via BraineacTPS Function Harness
GRN/BLK TPS SIG GRN/WHT
BLK/RED GROUND BLK/GRN
GRN/RED 5vref RED
Now the gauge all ways reads 0, pedal to floor or not, I try to calibrate 0% and get 0% then push pedal and get like 11 units, bar moves about 11% change of the graph at the bottom but glitches a bit (I did solder and shield wires). I did see the graph spike once or twice when i pushed it to wot.
I have tried everything, undid throttle cable, tried positioning tps, taking it of.
Is it possible I have a bad unit? Any way to test this?

SpartanSV

A vTPS is a potentiometer. Resistance changes as the throttle rotates. Voltage goes in one side and the resistance causes the voltage to change on the other side. Use a multimeter to measure the TPS input wire at the ECU. If the voltage is changing without rotating the TPS then that explains why the TPS % is creeping up. The next step would be to measure the resistance of the TPS to see if that is creeping.

shuiend

iTrader: (24)

Just so people are aware. Speedruino does not use any Megasquirt firmware. It runs its own firmware. They just happen to use TunerStudio as the interface program for the Speedruino. So there may be bugs in setting up the VTPS. It may also not be setup the same way MS does it.

ghia nut

shuiend, my apologies on miss communicating the firmware that speeduino uses.
Speeduino has not made any claims to be megasquirt, again my sincerest apologies in any confusion

I have put a volt meter to my vtps and Im 90% sure its messed up.
Pin A and B show some resistance change in ohms then OLs at a certain point. Then is makes random connections is all together glitchy as hell.
Im heading to the local autozone to pick up one on the shelf and hopefully we can get this thing going.