5. 0 vacuum problems - Ford F150 Forum - Community of Ford Truck Fans The HVAC vacuum system has its own vacuum reservoir, independent of the emissions vacuum system (which also has a reservoir) Both reservoirs are protected by check valves so opening the throttle doesn't empty them
Vacuum Check Valve - Ford Truck Enthusiasts Forums Need a good vacuum diagram or pictures to help locate this check valve and the vacuum line routing Thanks The bad news is that the vacuum tank and check valve are mounted inside the evaporator case in the engine compartment