well long story short, my cav leaks coolant. i've already changed the water pump, and the resivior cap seems to be in good shape. but today while driving home from work it did something funny. at first the low coolant light came on as always, then it would go off, then the check guages light came on and i was definitely in the red. i turned the heater on and nothing happens, which at this point the check engine light pops on. next thing i know, the needle jumps to cold at like the bink of an eye, and cool air starts blowing, then a few momnets later hot air would finally blow out, but only for id say 30 seconds to a minute if that. and when that would happen the needle would jump back to hot. at this point traffic is heavy and then i start to smell it..boiling over i guess. no steam was rising from under the hood and i was in heavy freeway traffic, but i was onl.y about 7 minutes from my house so i decided to go for it. i made it, but at this point i just don't know what to do. and im not a big fan of the shop, so any suggestion or helpful comments would be appreciated. thanks