I bought a 2013 Jetta back in May and recently found out the heat doesn't work. I think someone put some radiator stop leak and it might have clogged the heater core. Where the hell is the drain cock on the radiator? Or is there even one on the radiator? I want to drain some out and put in some stuff to flush it out. Thanks for any ideas, please let me know if Im barking up the wrong tree on this.