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EGR Valve Without BACKPRESSURE Transducer

  1. Check that all vacuum hoses are properly routed, all connections are secure, and that vacuum hoses are not cracked, crimped or broken. When engine is cold there should be no vacuum to operate the valve. If there is vacuum, check Ported Vacuum Switch (PVS) function. Replace if necessary. There should be no vacuum to valve at warm curb idle.
  2. Vacuum should be available at or above part throttle with engine at operating temperature. If vacuum is not available, check PVS and replace as necessary.
  3. With engine at idle, apply 8 in. Hg vacuum to EGR valve. Valve stem should move to open valve and produce a rough idle. If valve stem moves but idle does not change, remove valve and clean inlet and outlet ports with wire brush.
  4. With engine at idle, trap 4 in. Hg vacuum in EGR valve and hold. Vacuum should not drop more than one in. Hg in 30 seconds. If vacuum drops, replace valve.
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