Suburban 3/4 Ton 4WD V8-305 5.0L (1986)
Thermal Vacuum Valve - EVAP: Testing and Inspection
EGR Canister Purge Thermal Vacuum Switch (EGR-CP-TVS)
Below the switching point, Ports 1 and 2 should be blocked and no ported vacuum should be directed to the canister and EGR valve.
Above the switching point, Ports 1 and 2 should be open, allowing ported vacuum to be directed to the canister and EGR valve. Replace valve, if
defective.
