Subject: Intake valves and intake ports Information: Carboned-up valves in the engine can be reworked and...

Bulletin number

122-A6Z3V-03

Component

Engine and engine cooling: exhaust system: emission control: gas recirculation valve (EGR valve)

Summary

Subject: Intake valves and intake ports Information: Carboned-up valves in the engine can be reworked and cleaned using cleaning equipment. If there is a complaint about knocking combustion, e.g. during acceleration at high load, the condition of the intake valves and portsmust be checked before doing any other work. If the check shows that the intake valves and intake ports have carbon deposits and are dirty, they must be cleaned using the VAS 294 011 - cleaning unit. There should be no need to replace the components. Date of Introduction: The VAS 294 011 - cleaning unit can be ordered immediately for dealers. Remedial Action: The VAS 294 011 - cleaning unit is used for cleaning carboned-up intake valves and intake ports. Compressed air is used to spray a special granulatemixture into the intake port,where it loosens and removes carbon build-up. The dirty granulate is extracted during spraying using an industrial vacuum cleaner.

Owners of these vehicles have filed 100 complaints in the engine category.