A Chevrolet engine control module, or engine control unit, is the vehicle's on-board computer. The module is a hardware circuit board encoded with programming that regulates the vehicle operation, including the drive train and engine. When the engine control module fails, the vehicle can stall or fail to start.
If an engine control unit is damaged in a vehicle with an automatic transmission, the vehicle may not shift or it may jerk or stop as if there is a problem with the transmission. A check engine light that remains on is another indication of a faulty engine control module. A mechanic or technician can often reprogram a faulty engine control module, which is much less expensive than replacing the part. As of 2015, Chevrolet offers a performance-rated powertrain system that combines the engine and transmission, including the electronic control module.