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Ported EGR Valve

  1. Check vacuum hoses for correct routing. Connect a vacuum gauge directly to EGR vacuum source. With engine running, open and close throttle quickly to at least 1/2 open position. If gauge reading indicates vacuum, EGR vacuum supply is okay and vacuum port is open.
  2. If gauge reading indicates no vacuum, EGR vacuum port is plugged or restricted and should be cleaned. Disconnect vacuum hose at EGR valve, and plug hose. Connect a hand-held vacuum pump to EGR valve.
  3. Start engine. Apply 6-10 in. Hg to EGR valve. Engine speed should drop at least 100 RPM or stall. Vacuum should not drop more than 1 in. Hg in 30 seconds. Reconnect EGR vacuum hose.