Coolant Vacuum Switch Cold Open (CVSCO)

Fig. 6 Coolant vacuum switch cold open (CVSCO):

The CVSCO,Fig. 6, provides manifold vacuum to the system after a cold start until engine coolant temperature reaches a predetermined level. After the coolant temperature reaches this level, the switch closes and vacuum is cut-off from the air switching system. The CVSCO is mounted in the thermostat housing.