Tempo L4-140 2.3L HSC (1986)
Air Injection Vacuum Control Solenoid Valve: Description and Operation
The dual thermactor air control solenoid valve assembly consists of two normally closed solenoid vacuum valves (TAB & TAD), one controlling the
thermactor air bypass valve and the other the thermactor diverter valve. Both are vented when de-energized, sourced by the intake manifold vacuum
reservoir and controlled by an EEC system (they are also discussed in the EEC and MCU Systems diagnostic procedures).