Miata Turbo Forum - Boost cars, acquire cats.

- Hydra (https://www.miataturbo.net/hydra-58/)

- - TPS sensor fail (https://www.miataturbo.net/hydra-58/tps-sensor-fail-97059/)

I have had to recaibrate my throttle postion sensor three times as I work through my FMII install. Before I just order a new OEM one, are there better/cheaper options? It is a 99 motor in a 90 chassis.

id say check to make sure you are receving the 5v and ground to the sensor itself. test it and test it if the voltages change when opening/closing it manually. my 0.02.

Of course, since posting it has not acted up. I will check when it is misbehaving.

Check the ground connection at the front of the intake manifold. If this is not a good low resistance connection, the TPS signal will float around a bit.

Also, when calibrating the TPS (or any other sensor) always perform the calibration steps multiple times until the two values do not change when you press the calibration button. In other words, the throttle closed value may need to change a bit after the throttle open value has been set. I always go back and forth between closed and ope throttle, until is see the numeric values stop changing. I have also found a few bad ground connections this way because the two values never stop changing.

Thanks Ken, a bad ground is a cheaper fix than a new sensor. I will clean the grounds I have not disturbed during the build. It''s one of those things I tend to ignore, but shouldn't.