EGR System

Remove EGR valve and visually inspect for deposits. Check that diaphragm plunger moves freely. Connect EGR valve to vacuum source and apply vacuum; diaphragm plunger should lift off seat. Disconnect vacuum line, diaphragm plunger must return to valve seat. Replace copper seal on valve holder side and reinstall valve. Check entire system (lines, filter, connections) for leaks, deposits and restrictions.