Have a 1985 500SL/Euro that has not been driven in about six years. Car was repainted and interior totally replaced. Just now got it all back together. Engine was running fine last time it was drivable. Now it starts very easily but runs rough with extremely rich mixture. Have changed out the fuel pump and filter and got fresh fuel in the tank. Engine has very good compression and good ignition, new plugs.

My guess is that something in the mechanical fuel injection system has stuck or stopped up. Having a difficult time finding any diagnostic info. on the system. Any suggestions on an approach to solve this problem would be greatly appreciated.