I still like the flooded engine theory. I’m old-school, and the engine acts exactly like a flooded engine would act. High tech certainly can throw a monkey wrench into such a theory, but consider this. Since the car is only driven a short distance, the engine doesn’t build up much heat. If it only sits a few minutes, the flooded cylinders don’t have time for the fuel to dissipate. If the car sits for a long time, say two hours, it starts just fine. Also, when the car is driven for a reasonably long time and distance so that it heats everything up, it will start again without a problem, I theorize, because the fully heated engine/compartment, etc. dissipates any extra fuel pretty quickly. I admit, it’s an old-school theory, but it fits.

Anyway, how can I tell if the injectors are worn? I don’t want to launch into an expensive replacement if it isn’t needed. The car has been to two competent mechanics, one a Mercedes specialist, who have not found any fault codes or other tech problems that would account for the strange behavior.