Update: I took the car to Al Bernal at Mercedes Connexion. He set the timing, adjusted the valves, set the injector pump timing, cleaned the injectors and fixed a few vacuum leaks. The car runs much better. A chassis lube + re adjusting the wheel bearings fixed my wandering problem. He also adjusted the tranny shifting and the car shifts silky smooth now. The best part is the price he charged me! He doesn't for the time spent diagnosing the problem... It did take some time for him to do all the work, but was worth the time.