Severe Hesitation in 420SEL 1989

[xsohaib]

OK, when the car has been sitting for atleast 6 hours or more and I start to drive the car, the following happens
As long as the temperature is below 70 degrees it hesitates between 2000 and 2500 rpm's. It hesitates quite heavily more like jerks, and there seems to be severe loss of powere during this time. However as soon as the temp gauge reaches the 70 degrees mark (just below the 80 dgrees) it seems that the car is as if on a turbo (the power comes back and evrything is fine). The car has 178K miles and I used sythetic oil for the first time in this kind of a cold weather in Alaska (i.e. first time synthetic and first time cold weather, the car was in Texas before). The outside temperatures are in the 20's. Any ideas/suggestions/advice etc would be greatly appreciated. Thanks in advance

Sohaib