I just installed my new power fc and am having an issue with the speedometer in the car now. When I first start the car the vehicle speed shows zero but the moment the apexi starts to drop the idle down from cold start high idle the speedo will begin to follow the tach. Rev the engine and the speedo will follow with the tach when the car is stationary. I swapped back in the stock Ecu and the problem goes away, no abnormal speedo movement at all. I've verified removal of the correct 4 wires from the harness for the power fc install and bought the power fc and commander brand new. Thoughts? Bad power fc?

 

Im dealing with the exact same issue on an FD I have right now. Same issue with two separate PFCs, both do not cause the issue in my personal FD. Install stock ecu and no issue occurs. Any guesses?