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Vacuum Spark Control Delay Valve

  1. Connect a tee fitting at ports "1" and "4". Connect vacuum gauge to each fitting. Start engine. Vacuum should be equal at both ports.
  2. When throttle is suddenly depressed, vacuum at port" 1" will instantly decrease and vacuum at port "4" should be maintained momentarily. If valve fails these tests, replace valve.
    Fig 1: California 4-Cylinder Spark Control System
    G09337305Courtesy of CHRYSLER GROUP, LLC
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