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Ported EGR Valve

  1. Ensure engine is at normal temperature. Disconnect vacuum hose at EGR valve. Connect a vacuum pump to EGR valve. Start engine. Apply vacuum to EGR valve. If engine stalls and gauge holds vacuum, EGR valve is functioning properly.
  2. Connect a vacuum gauge to EGR hose. Increase engine speed to about 3000 RPM. If vacuum is shown on gauge, system is functioning properly.
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