I have never had any issues with any of the MS I built but I also dont have my coils hooked up either. Try connecting the coils to the stock ecu and see if the problem persists. If it still persists then it must be a sensor or wiring issue.

My setup has the MS ecu installed in the Console, Ground goes direct to the battery point where the ground cable connect to the frame. Wiring exits the firewall behind the washer bottle and is routed with the factory wiring.

Using my car as a test subject i have tested roughly 8 v2.2 ECU's and 6 v3.0 ECU's.

Mummolo tried the 12v at the Crank sensor and still had issues.

Terry