Poor Running when cold, Please Help

["dcsj4465" <dcsj@xxxx>]

I have a friend who is having problems with drivability when the 
engine is cold. Now it seems to be getting worse. The problem seems 
to persist with cold ambient temps. When ever the eng is cold he has 
to let it warm up a couple minutes otherwise it will buck and jerk 
pretty bad. It usually clears up in a mile or two. Recently he had to 
drive nearly 10 miles before it cleared up. That day the morning temp 
was in the 20's.(DULUTH,MN) The last time I talked with him he had 
driven the car up the Northshore of lake Superior about 20 miles with 
it running poorly all the way. After he arrived at his destination, 
he gave the throttle spool some quick revs as if too try and clear 
the engine out then shut it off. He drove home an hour later and all 
was fine. This is a mystery! Any suggestions wound be helpfull. Also 
the frequency valve appears to be buzzing just fine. Is there a most 
likely item we should be looking at that would cause this senario of 
events?

Thanks, Dennis 5180