Hmm... Same here
I have the same symptom on my 92 300e (2.6).. On most attempts to start the car, the car hesitantly shakes/runs rough for that first initial second-or-so of startup, then it runs great.. I replaced plugs and ran Techron Fuel cleaner in the tank, which hasnt helped.. I too am considering replacing the injectors, because of their low price.. (and, they *appear* at least, to be easy to replace)... What other areas of the M103/M104 engine could cause this odd initial rough running of the engine during startup? Could one suspect the fuel pump(s) perhaps?? (don't these cars have like... 2 pumps?) I'm stumped!
92 300e 2.6