Hello, I had an oil change before about 700 km. Yesterday after about 25 km of road I turned off my P. to make a short toilet break. ALs I came back and started, suddenly the engine control light went on – with the message: Error exhaust gas – workshop! Some restarts could not delete the error – therefore I think it is rather less an “electronic spinning”. What I still noticed is that I have brownish mud on the oil cover – although I left an oil change before about 700 km. In the previous 35,000 km I NIE, not once brownish mud on the oil cover. (btw. during the inspection 1L cooling water was refilled – until now it is still on MAX, no oil entry or similar. Therefore I think that the ZKD is in order, only right after the car just comes out of the inspection.) 1. What could be the error message? Particle filter, AG, differential pressure sensor etc.?