Fuel Cutoff Mode

The PCM cuts off fuel from the fuel injectors when certain conditions are met. This fuel shut off mode protects the powertrain from damage and improves driveability. The control module disables the injectors under the following conditions:
^ The ignition is OFF, prevents engine run-on
^ The ignition is ON but there is no ignition reference signal, prevents flooding or backfiring
^ The engine speed is too high, above red line
^ The vehicle speed is too high, above rated tire speed
^ During an extended, high speed, closed throttle coast down, reduces emissions and increases engine braking