Find where that heater plug is.
If it's working, that'll take care of a lot of problems. On my Pontiac, as long as I had the heater plugged in, it never failed to start, and
since I always used the fuel additive in the winter, it never failed to get me the 57 miles one way to work and back...
...except for the time the nut behind the wheel let the thing run out of fuel...
(Priming that particular diesel is a ROYAL pain...)
...and it would get 35mpg all day long. A/C running. At 65 mph.