Liquidog

Hey all. I'm having an issue where no matter what I do, the TPS values in TunerStudio don't change during calibration. Whether or not I have the pedal pressed, the numbers don't change. I'm not 100% on how the wiring works on the VTPS unit itself, but changing around the order of the connections every which way doesn't change the problem, it just changes the value. So it could be stuck at 63 for no throttle and 63 for WOT, or it could be stuck at 965 for no throttle and 965 for WOT, but there's never a difference in the values no matter how I change the VTPS wiring connections at the harness.

The car is a 1990 with a DIYPNP Megasquirt, 1.5 board. I followed the documentation for setting up VTPS as shown here:
https://www.diyautotune.com/support/...3-mazda-miata/

TPS SIG to 4L (did not jump TPS SIG to ground since that appears to only be for stock TPS)
VREF to 1N

I'm sure I'm making a hash of the VTPS connection, but shouldn't I still be getting a different value at WOT? I've done this with the laptop in the engine bay, operating the throttle by hand and ensuring the post in the throttle body is actually spinning the ring inside the VTPS unit. Still no change in values.

This leads me to believe I have screwed up some of the connections in the DIYPNP. Did I miss something here? Anyone have any pointers? Some photos for reference.

Other details: car cranks but won't start, Tach in TunerStudio shows 65000 rpms, apparently my basemap from DIYautotune is too old for my v3.4 firmware, tried the save-as and reload trick to get that to go away but no dice.

Matt Cramer

65000 RPM is a config error. Please upload the tune that's giving you this - you won't be able to straighten the rest out.

Liquidog

Thanks Matt, I'll upload the tune file when I have access to my tuning laptop tonight.

Liquidog

Hey Matt, here's my current tune. The car is a 1990 with a 1.8 swap currently running stock 1.8 injectors, all from a '94. Running the GM IAT and an AEM UEGO wbo2 wired in at the ECU harness and in place of the stock o2 sensor on the stock downpipe. Trying to get the base tune running before I take the car apart to go turbo. Thanks!

Matt Cramer

You've accidentally loaded your DIYPNP with firmware intended for an MS2 V3.0 or V3.57. Please reload the firmware and make sure to specify it's a MicroSquirt Module.

Liquidog

Thanks Matt, reloading the firmware fixed the issue. Not sure how the wrong firmware got loaded but this time the loader chose the right ini automatically. In any case the 65k RPM issue went away and I'm not getting all the errors. I was also able to calibrate the VTPS in TunerStudio. The car still isn't starting but I think it's probably a different issue so I'm going to start a new thread. Thanks again for the help.

Sindrerystad

can you please provide a marked photo for where all the «jumpers» go for vTPS? Currently stuggeling with this myself!
many thanks!