Ok I have had this problem for a while now.

My 1987 300E seems to have a hesitation and shuddering when it is started up. Sometimes within the first mile or so the car wants to cut off but once u fiight thru the problem by giving gas it runs fine. This problem is worse when it is cold outside. I mean southern california cold like 60. I tried using chevron techron fuel system cleaner and it helped about 15% but the problem largely persists. Also the car sometimes when cold the engine races back and forth to 1500 rpm without me touching the gas.

Any help is greatly appreciated.