Pretty much had the exact thing happen to me yesterday. Driving, suddenly
no power, very slow, pulled over stopped, would not start. I was hungry so
I went to eat, came back it started. Drove to my shop, stopped again about
a block away. ( drove about 12 miles to the shop. ) Vehicle '01 e430

Problem was Crank position sensor.

Anyway today I picked it up from the shop: $ 220.00 part & labor.

Note: Normally I would have bought the part from Arizona ********
** $ 40.00, the shop charged 1 hour labor for the install.

So I could have gotten away for $ 120.00. Have not checked to see
if this is a easy DIY, if so a $ 40.00 part & my time to install ...

Does it get better than that ... we are talking German machine here ...

CLK with 23K, owner fixes the sensor you will be in good shape.

I also have a '02 CLK 430 zero problem with mechanical issues. Only issue
I have had has been passenger seat getting stuck ( would not go back & forward ), and misc issue with my clock comming on & off or dimming
when the blinker is on. Vehicle has 42K on it.

For some reason I do not think about a blinking clock when enjoying the
ride, power & class of a CLK.

Jump the opportunity while you have it.