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Vacuum Delay Valve

  1. Disconnect and remove vacuum delay valve. Connect vacuum gauge to delay valve. Using an additional piece of tubing, connect delay valve directly to intake manifold vacuum. See Fig 1.
  2. Start engine and operate at idle speed. Note reading on vacuum gauge at idle. Disconnect manifold vacuum from delay valve. Record time required for vacuum gauge to drop 11.8 in. Hg from reading recorded at idle. If time is not within specifications listed in Vacuum Delay Valve Specifications table, replace vacuum delay valve.
    NOTE: If vacuum delay valve is stamped with an arrow, install with arrow facing intake manifold vacuum source.
    Fig 1: Testing Vacuum Delay Valve
    G09313929Courtesy of MAZDA MOTORS CORP.
    Vacuum Delay Valve Specifications

    Application Time (Sec.)
    GLC 7.5
    GLC Wagon
      Man. Trans. 4-6
      Auto. Trans. 6-9
    626 16-24
    B2000 8-12