ok so my heat has been bad ever since i got the car. it will barley defrost the wind sheild. and to drive it in the winter, you have to wear insulated gloves/boots. i tried flushing the heater core, and nothing changed. I found this jug that has some type of fluid in it, and says "subzero " on it. could this be my problem? what is this? it is located on the riders side under the heater fan motor.

 

Try switching the hot and cold switch back and forth. You should hear a door opening or closing.

That unit is called a logicon and 7's are known to have problems with these.

 

Nope, that piece isn't your problem. That's the sub-zero start assist reservoir. From the factory it would normally inject a little bit of antifreeze into your engine when it gets cold enough outside. It was a bad idea so no one uses it. It wont hurt anything to just leave it alone, but if you want you can remove it.

As for your heat.. What freemanrx7 said sounds like a good starting point.