I had my throttle actuator replaced under warranty in 1997; it was a part that had been recalled on my model years earlier. At the time, my 1991 300E started stalling out as I braked for the first two stop signs I came to in the morning. Both stop signs are very close to my house, so the car was not yet warmed up. It never happened during any other stops I made (stop signs or traffic lights)after the first 2 stops. However, my car never ever stalled at all on the return evening trips; I thought this was funny, because I also had to stop at stop signs with no warm up in the car during the evening. Go figure! As with all tempermental and individual cars, your symptoms may be slightly different.
I know the dealer checked the fuel injectors, performed code checks and looked into the electrical system overall. But basically they knew of the throttle actuator recall and were just being thorough to ensure that nothing else was wrong in addition. I know on my invoice it says "replaced throttle actuator" under the labor portion. Then, under the parts area, it says "switch, fianl." I don't know if the switch is a separate part from the throttle actuator or what. When I questioned the dealer, they simply muttered something about "fuel injection," "$900 part," "defective throttle slide," and "electronic part." Only because the work was under warranty did I decide to leave it at that and go merrily on my way. If I was paying for the labor and part(s), I would have wanted deeper clarification.