For model year 1994, General Motors has completed the roll out of the 6.5L Diesel Engine, with the introduction of the light duty certified naturally aspirated and turbocharged engines. At the heart of the expanded use of the 6.5L is a new electronic powertrain control system. The objectives for this system were to produce an engine that has less variation, is easier to assemble, low cost and capable of meeting both heavy and light duty future emissions requirements. Control features include Fuel Quantity and Timing, EGR, Wastegate, Glow Plugs, Transmission, Cruise Control and Diagnostics. These features are performed based on the following devices:Electronic Rotary Injection PumpElectronic Foot PedalBoost SensorCoolant TemperatureInlet Air TemperatureFuel TemperatureCrank Position SensorBarometric Pressure SensorEGR Feedback SensorCatalytic ConvertorVehicle SpeedThis paper will cover the highlights of the development and optimization of the control features, combustion process, emissions and drivability for the wide range of engine applications.