Abstract: An emissions control system for eliminating or substantially reducing the levels of hydrocarbons, carbon monoxide, oxides of nitrogen and other noxious components in the exhaust gas flow from the internal combustion engine of an automotive vehicle or the like to permissible levels. The system includes a reaction device adapted to be connected to the exhaust gas flow from the engine and having one or more ceramic reaction elements therein which cause the undesirable components in the exhaust gas flow to oxidize, disassociate or otherwise become innocuous before being discharged into the atmosphere. An engine driven air pump supplies air under pressure to the reaction device, and a spark plug is mounted in the device and connected to a suitable high voltage source so that a spark is maintained across the electrodes of the spark plug when the engine of the vehicle is either cold or idling, or when the vehicle is decelerating.