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EGR Valve With Integral BACKPRESSURE Transducer

  1. Clamp drive socket wrench into tailpipe. Socket outside diameter should be about 1/16" less than tailpipe inside diameter. Socket drive hole should be covered and socket should be inserted into tailpipe with open end facing out to ensure proper backpressure.
  2. Do not block tailpipe fully or run engine faster than idle for prolonged periods of time. Be sure to remove socket from tailpipe at end of test.
  3. Idle engine and apply vacuum to EGR valve gradually. EGR valve diaphragm should move smoothly and rough idle should occur. Trap 6 in. Hg vacuum in EGR valve and hold. Vacuum should drop more than one in. Hg in 30 seconds.
  4. If vacuum does not drop or diaphragm does not move, replace valve. If diaphragm moves but idle does not change, remove valve and check for plugged inlet and outlet ports. Clean inlet and outlet ports with wire brush and install valve and retest.
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