This is atypical behavior.

Check the usual suspects, such as a plugged air filter, low fuel pressure, etc.


Does car sputter, miss, smoke, not much to go on with your limited desription.

Jim

__________________
14 E250 BlueTEC black. 45k miles
95 E320 Cabriolet Emerald green 66k miles
94 E320 Cabriolet Emerald green 152k miles
85 300TD 4 spd man, euro bumpers and lights, 15" Pentas dark blue 274k miles