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1977-78 230 Models

  1. Disconnect Brown vacuum line at carburetor and Gray vacuum line at intake manifold. Connect Brown vacuum line to intake manifold connection. Engine should run rough or stall. If not, ensure that all EGR system vacuum lines are properly connected.
  2. The carburetor Brown vacuum line MUST be connected to angular port of thermo/vacuum valve. The Brown/Purple vacuum line MUST be connected to vertical port of thermo/vacuum valve.
  3. If vacuum lines are properly connected, check all vacuum lines for leaks. Clean the carburetor 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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