Read up on the reverse relay action of the fuel pump.
When the brown red wire is grounded, as in a stalled engine situation that makes the air flow switch become grounded when it closes, it actuates the coil and kills power to the fuel pump.
Here is a drawing I made up for microsquirt for someone, using the existing 78-83 wiring. Fuel only setup.
MS2 wiring is similar but has different terminals and wire colors at the ECU connector.
You’ll need to figure out and wire in your MSD as well.
