wats up guyz, i recently bought a 2001 c320 and i have been exprencing a few problems. 1. the first week i got the car, while driving the car shut off on me twice and i would feel a slight shutter when iam at a full stop, 2. i changed the spark plugs and did a oil change. after changing the spark plugs the car has not shut off on me but the shaking/shuttering was still present. 3. took the car to a shop thats known for doing work on german cars, they ran a dignostic test , told me two cylender are misfiring, could be that the wires or coils are bad.4.they repalced the coils and the wires on both cylenders, but i can still feel the shaking?
if anyone has information would be great. thanks!!!

the car is a 2001 c320
has 84000 miles
no check engine