I have a Passat 2013 tdi SEL. Contrary to some message boards - it does not need to be freezing temperatures for this to appear. The prevalent use of this in diesel vehicles today stemmed from the compliance of automakers to the Euro 6 regulations in an effort to mitigate the air pollutants commonly produced by cars. Your car wont start again if you run out of AdBlueTM after you turn off the engine. To tune ECUs for all types of vehicles, from trucks and tractors to heavy road cars like the Porsche 991 Turbo, Ecufalsh has a skilled staff of software developers and is connected to other tuners and programmers all over the world.