Help, don't know what i broke.
 

Okay so i was replacing my spark plugs and i accidentally snapped this plastic hose on the passenger side of the engine compartment. the PLastic hose came out of this black ball looking thing that sits by the radiator, on the side wall. if anybody knows what this is it would help, my truck was running beautifully but now it's running like shit and i think it's a vacuum leak from the plastic hose i broke, but i'm not sure cause i don't know what that black ball thing is.

97 ford ranger 4.0L V6 5-speed.

You broke the vacuum line to the top of the intake. It comes from the Vacuum booster behind the master cylinder.
Just go get another piece of hose from the hardware store and reconnect it to each side.

thank you will do.

well i replaced the vacuum line.... $0.37 at pull a part, but now my engine isn't reaching proper operating temp, could it be the thermostat, it got pretty cold here, i'm wondering if it's stuck open.

I need more than just "not reaching temp"
Where does it stay at once you've been driving for about 10-15 minutes? Does the heater blow hot air? Have you checked your Radiator fluid level?