Man I have the same exact problem with my truck. I live in New Orlean and we go through a few weather changes of a 30-40 degree change in a day or two. When the truck warms up it runs great but if the guage is below the cold line it will run rough and die and I will have to restart it and let it warm for 30mins. If I start it in morning and sit in the truck to try to keep pushing fuel through the engine(rev it up) the RPM's will just barely go above 1000. I could floor it and it has no power. But again like I said when it has warmed up it is running great. No check engine lights on or anything. ANy goes?