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PVS with 3 Connections

  1. Disconnect EGR vacuum hose from PVS and connect manifold vacuum or external vacuum source to lowest port on PVS. See Figure .
  2. Detach distributor supply hose from center port, and attach vacuum gauge to center port.
  3. Start engine and warm up until engine operating temperature is reached. If no vacuum is present, replace PVS. If present, PVS is okay.
Fig 1: Cutaway View of 2-Port PVS PVS will open when engine reaches operating temperature.
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