EGR System - BMW: Maintenance: Notes

Service EGR system every 16, 000 miles as follows:

1. Remove and disassemble EGR system completely. Remove deposits in tubes, connectors, filter and valve by means of appropriate tools. Avoid damaging surfaces of components with sharp tools.
2. Test EGR valve as described above. Reassemble system using graphite grease on threads of tube assemblies. Start engine, if engine runs at idle speed, diaphragm valve assembly is closed. Sprinkle water on tube section connecting valve with intake manifold. If engine speed decreases, system is not tight. Open EGR valve by connecting to outside vacuum source and sprinkle tube from exhaust manifold to valve with water. If engine speed decreases, system is not tight.