did that already it helped a lil but when its like 0 or lower it has basically no heat at all and when im stopped at a stoplight i get no heat compared to a lil heat driving. i got 70k miles on it and the guy i bought it from only drove it in the summer so im thinking the heater was barely used so it has a bunch of junk in it.
It shouldn't have "a bunch of gunk in it"...have you checked/replaced your radiator cap or thermostat? If those are good and you're sure you got all the air out (sometimes it takes a few times to bleed it), then the next usual problem for what you're describing is to replace the water pump.
As for your original question about flushing the fluid though, you can't just put a hose in the radiator and call it good. I think Prestone makes a kit you can install in one of your heater hoses so you can actually flush the system, but the problem you're going to run in to is dumping of coolant all over the ground which is an environmental concern (and usually illegal). Chances are, you don't have the ability to properly flush the system...you'd have to take it to a shop and have them draw the sytem down and then replenish it...but not all shops have the right equipment for that either...
