Ported Vacuum Switches: Description

Ported Vacuum Switches (PVS) are temperature sensitive vacuum controlling devices. PVS valves have 2, 3 or 4 ports. An electric PVS is used on some engines with catalytic converters and air injection. The coolant and exhaust gas recirculation PVS valves have 3 temperature ranges. See PVS COLOR CODES CHART . The electric PVS is a combined vacuum switching and electric signalling device. There are 2 versions of the electric PVS valve. One with normally closed contacts and one with normally open contacts.