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Vacuum Check Valve: Testing

  1. Connect hand vacuum pump and hose to "check" side of valve (opposite black side). Apply 16 in. Hg (54 kPa) of vacuum. Valves are good if vacuum remains above 15 in. Hg (50.6 kPa) for 10 seconds.
  2. If valve passes test, reinstall in original location. Start engine, check for vacuum leaks and proper engine operation.
NOTE: Be sure valve is installed in correct direction, or engine operation will be affected.
Fig 1: Vacuum Check Valves
G113238Courtesy of FORD MOTOR CO.