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1977-79 All Other Models

  1. Disconnect Brown vacuum line at EGR valve. Slowly increase engine speed. Above approximately 1200 RPM, engine should begin to run rough and/or stall. If not, ensure that all EGR system vacuum lines are properly connected to exhaust pressure transducer and intake manifold.
  2. Ensure that connections on exhaust pressure transducer are properly connected. The vacuum line connections of the transducer have color coded rings. The vacuum lines attached to transducer must have the same color code.
  3. The Red vacuum line MUST be connected to the angular port of thermo/vacuum valve and the Red/Purple line to the vertical port of thermo/vacuum valve. Check all vacuum lines for leaks and clean the vacuum pick-up connection with compressed air. If engine still does not run rough or stall, test individual components of the EGR system.
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