hi everyone I'm new to the site i am a 17 year Benz and BMW tech i had the same issue on my mini cooper 2010 1.6 non turbo i did the timing chain vanos gears intake and exhaust and vanos solenoids what it ended up being was a shock to me there is a non return valve under the vanos solenoid that controls oil pressure to the solenoid and to the vanos gear the spring in that non return valve fell out and was not holding pressure i got a new one for about 30 bucks put it in and my exhaust timing came right back and i was able to do a vanos adaptation and get rid of all the code car runs perfect now i hope this helps someone i have seen a lot of people looking for a fix to the codes 283D-2845