Monte Carlo V6-262 4.3L VIN Z TBI (1985)
Thermal Vacuum Valve: Description and Operation
EGR EFE Elec. Module Retard Dist. Thrml. Vac. Sw.
When engine coolant temperature is below the switching point, this switch receives manifold vacuum from port 2, which is directed through the TVS
from port 1. Port 3 is vented through port 6 while ported vacuum at port 4 and distributor ports are sealed.
When engine coolant temperature is above the switching point, the distributor port 5 receives manifold vacuum from port 1. Port 2 is now vented
through port 6, while port 3 receives ported vacuum from port 4.
