Okay i've been doing alot of reading on here and I know that my heater core is bad. I have been trying my best to find a 99 Blazer Heater Core How To. But I cant does anyone have any information or link to a How To change it?

 

https://blazerforum.com/forum/showth...ht=heater+core

 

If your heater core is only plugged, but not leaking into the cabin, try backflushing the heater core. It's really easy and will only take 45 minutes total. I disconnect the heater hoses from the engine, then hold a garden hose against one end of one of the heater core hoses ... it pushes the brown crud out of the other hose and all over the driveway ... then switch to push it the other direction ... do this until you see nice clean water coming out. These heater cores seem to work like a 'P'-trap under a sink, they are one of the lowest points in the system, and the solids tend to land there. The crud that comes out has the consistency of clay, and could be deteriorating gasket material or possibly the Dexcool breaking down. GL

 

If your heater core is leaking and you have to replace it, get a repair manual, (Haynes or Chilton) will do. The entire dash has to come out and there's way too many steps to remember, you'll need the info at hand.You can pick up a new core at most auto parts stores. If you've never done it before, plan on 6 to 8 hours. Good luck.

 

I just replaced mine not too long ago in my 2000. Steam in the cabin, film on windows the whole 9 yards. (If you haven't done this already), the entire dash needs to come out and there's about 18 million little screws you gotta remove in order to do so. I didn't use a repair manual though, just read a lot on here beforehand and I did it in about 8 hours. Check out the pics on my profile if you wanna see what it looks like.