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Vacuum Spark Control Delay Valve

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  1. Connect tee fitting at ports "1" and "4". Connect vacuum gauge to each fitting. Start engine. Vacuum should be equal at both ports. See Figure .
  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: Spark Control System (4-Cyl. - CA Models)
G9985Courtesy of AMERICAN MOTORS/JEEP CORP.