Here is a complete list of Audi A4 Diesel engine codes. It can help you order the right engine for your A4 Diesel. It is always good to know the engine code as it can also help ordering other engine parts and ancillaries like cylinder head, gearbox etc. Other information you can know is the power, BHPs, year, Aspiration, cylinder valves and RPM of your Audi A4 Diesel engine.