MSefi.com read only forum (Jan.15,2018)

FYI to all Saturn tuners... If you are using a MS setup in full standalone mode on an OBD II Saturn (manual transmission) take note. You'll probably be using the stock ECU to run your speedometer and fuel gauges. In doing so the stock ECU will be getting a wheel speed signal from the transmission and calculating the signal for the speedometer. If you notice your gauges tweaking or blipping this is because the stock ECU is no longer getting an RPM signal from the engine. The stock ECU runs some kind of code to keep the Speedometer in sync when accelerating. If the ECU is getting a wheel speed signal AND it knows you are in gear AS WELL AS not having a tach signal it will cause the ECU to blip out on acceleration. The fix is to make sure you disconnect the one wire on the reverse/in gear switch on the top of the transmission. That way the stock ECU thinks you are in neutral all the time.

A.J.

is there a way to connect th speedo without the stock ecu ?

Not yet. But soon with the GPIO board. You should be able to set the GPIO board up to run the speedometer, tach, coolant temp, and fuel level gauges. Especially useful if you have changed your wheel size from stock.

A.J.

oh thx but the only thing that actually need to be run with the pcm is speedometer all the rest is wired and work well