RAM 2500 Truck 2WD L6-5.9L DSL Turbo VIN 7 (2001)
Vacuum Check Valve HVAC: Testing and Inspection
1. Remove the vacuum check valve. On these engines, the vacuum check valve is integral to the engine vacuum pump nipple and is threaded into the
vacuum pump. The vacuum check valve must be removed in order to perform the following tests.
2. Connect the test set vacuum supply hose to the a/c heater control side of the valve. When connected to this side of the check valve, no vacuum
should pass and the test set gauge should return to the 27 kPa (8 in. Hg.) setting. If OK, go to step Step 3. If not OK, replace the faulty valve.
3. Connect the test set vacuum supply hose to the engine vacuum side of the valve. When connected to this side of the check valve, vacuum should
flow through the valve without restriction. If not OK, replace the faulty valve.
