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PVS with 4 Connections

  1. Disconnect vacuum hoses at PVS valve. Connect vacuum gauge to top port of PVS. Connect external vacuum source to 2nd port. See Figure .
  2. Start engine and warm up until engine operating temperature is reached. If no vacuum, this portion of PVS is damaged and valve should be replaced. If vacuum is present, proceed to next step.
    Fig 1: Cutaway View of 3-Port PVS Warm engine should indicate vacuum at center PVS port.
    G8779
  3. Connect gauge to 3rd port and vacuum supply to bottom port. If vacuum is noted, PVS is okay. If no vacuum, replace PVS.
Fig 2: Cutaway View of 4-Port PVS Connect vacuum gauge to 1st & 3rd port to check PVS.
G8780
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