Thermactor Controls

These controls direct the flow of air from an air pump to either the exhaust manifold, the catalytic converter, or the atmosphere. On all models, a pair of solenoid valves control vacuum flow which operates a Thermactor Air Valve assembly. These valves are called the Thermactor Air By-Pass (TAB) and Thermactor Air Diverter (TAD) valves.

In normal operation, the air is injected in the catalytic converter to improve reduction of emissions. When the engine is idling or decelerating for long periods of time, air is diverted to atmosphere. When the engine is first warming, air is injected into the exhaust manifold to help heat exhaust gases before they reach the converter.