Probably because when it's warm, even poorly atomized fuel will burn but it has a much harder time when it's cold and especially when the GP goes out.

__________________
-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250