Car was running fine yesterday, its cold outside

How cold?

Do you have normal fuel pressure when you first crank it ?

Fan stop working,check fuse ,try to move key when start car,slightly up and down do not turn off.

Try bleeding any fuel lines in case you have air in the system.

check oil levels look for any obstructions around blades watch your hands

The voltmeter should only go as high as 14-15 volts when the engine is running. I would check for a poor connection between the battery and starter.

Starter or ingition switch problem. Let me guess, you live in a cold region? If yes, then I'm betting money on the starter. The cold does a number on starters. The colder it gets the more likely they go out. Lol, happened to my friends truck Tuesday and mine this morning. That's what we get for living in -10 degree weather right?

Sounds Like Temp Control Problem--It Can Be Scanned For Function Problem(s)

could be a vacume leak. check hose for cracks or lose conections.

Adjust choke assembly. Good mechanic, 5-10 min.