[olddog]

All I have delved into was the 1989 - 1993 Ford OEM ECU. It has a table to correct the injectors for voltage drift. The speed at which the tiny solenoid valve opens in an injector is proportional to the voltage applied. So if the voltage is low, the injector has to be turned on longer to put out the desired amount of fuel. Shorter if the voltage is high. If I recall the table goes from 10 volts to 14 volts. If the voltage drops mush below 10 volts the ECU will shut off the engine as if the key was turned off.