Car continues to run horrible in cold outside temperatures

This car belongs to my grandma. Last winter and this winter the car stalls and shuts off in outside cold temperatures. Once it hit the forties the car barely works. We suspected the fuel injectors. Once it is running pull each connector and than plug back in while car is still running. The car does not seem to stall, it just stops running. My husband believes it to be a fuel issue. And I am running out of time as he leaves for Florida soon. I read several of your answers. Thought maybe I would ask your opinion.