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WASTEGATE Activating Diaphragm Check

  1. Check that activating rod is in place and retained by clip. Correct as required. Remove lines from diaphragm and attach a vacuum source to vacuum side of diaphragm. Apply 25 in. Hg vacuum and trap. If vacuum drops below 18 in. Hg after 60 seconds, replace wastegate activating diaphragm.
  2. Install an external pressure source to the pressure side of the diaphragm. Apply 5 psi and trap. If the pressure drops below 2 psi after 60 seconds, replace wastegate activating diaphragm. If pressure does not drop, release pressure but do not remove pressure source and hose.
  3. Install a dial indicator to measure travel of wastegate activating rod. Apply pressure VERY SLOWLY until dial indicator shows 0.015" movement. Pressure gauge should read 6.8±.5 psi. If wastegate arm does not meet specification or move freely, replace wastegate activating diaphragm. See Fig. 3  .
Fig 1: Checking Wastegate Activating Rod Travel
G09320103Courtesy of FORD MOTOR CO.