[denisond3]

You bleed them of air by just ensuring the radiator is full to the filler neck, then putting the cap on and going for a drive - with the heater on. By the time you get it up to 40 mph it will have moved any air to the top of the radiator. From here the air bubble should either be pushed into the coolant recovery tank, or when you park it and the engine cools, it should draw liquid from the coolant recovery tank into the radiator. Basically you should see coolant right up into the filler neck, anytimg you remove the radiator cap on a cold engine. Removing that cap on a hot engine can let coolant blast out and scald you.
Any of the connectors on the wiring harness are replaceable, though not all of them are easy to find for sale. Somone would have them though, like the dealer if no one else. The connector on the sensor itself would only get replaced via a new sensor.
If it cranks a long time, something is definitely amiss. Temperature sensors are a likely item to 'age'. Try turning the ign key on and off a couple of times without actually starting the car. This will make the fuel pump run, and ensure there is fuel in the fuel rail, in the event you have a fuel pressure regulator that is leaky.