Fully checkout the ignition system and when you replace the plugs and wires, use the ORIGINAL plugs that were specified in the owners manual and not for example a large electrode version (a plug with a zero on the end of it) that Mercedes will give you at the dealership. Do not use platinum plugs unless you want to guess if those will work, your results will vary with those.

Use the CORRECT plug wires from Mercedes/Bosch, not aftermarket ones. The resistance in these is setup properly. Most aftermarket wires I've seen are crap anyway and have the wrong resistance.

If you don't do the above correctly, you'll spend time chasing those issues just to return to the original issue. Speaking from experience.

After you have gone through the ignition system, then you can go to the fuel system. Once you are confident the ignition is straight and the car isn't misfiring heavily on acceleration, you can put some Chevron Techron in the tank (the big bottle) when the tank is empty and then fill it. Then drive the car hard. I swear by Techron, it's for me the best of the bunch for fuel injector cleaners and yes, it really can solve fuel and intake dirt problems in there. You need to drive the car hard. But if the car isn't driving right, use your own judgement because driving it hard with something up in there may cause its own damage (such as heavy misfiring damaging your catalytic converter).

Yes of course check for vacuum leaks and the standard array of issues such as the air cleaner, etc. It's OK to check on the oxygen sensor also-- that's an easy fix/swap-out. Be sure to splice that wire very nice and tightly and make a VERY good connection. The O2 sensor gives a very low voltage, the connection has to be nice and tight.

If none of the above solves the problem, then onto the fuel system. First verify the kind of Bosch fuel system in your car. Mine (an 84) is K-Jetronic. I think yours is electrical, I don't know maybe KE-Jetronic. Then learn about that fuel injection system (injectors, fuel distributor, etc). The first and easiest/cheapest place may be to check your fuel injectors. Be sure to replace new seals/etc when you remove/replace them. You can introduce vacuum leaks there that will plague you later as well.