I have had a mystery leak for some time now, and finally found it. Its the hose that comes out from the firewall and its the one on the left. There are 2 hoses going into the firewall and this one that needs to be replaced is on the left. Which one is it? Thanks

 

One of the heater hoses most likely.

 

I figured it to be one of em but was just wanting to find out if it was the Bypass or Heating hose. I guess when I go to AutoZone I can look at the 2 and figure it out.

 

Bypass... Don't know exactly what you mean by that... If they are two hoses that are about 1" outside diameter going into the firewall, then they are the heater core hoses. What are you working with?

 

They have to be heater hoses, but sometimes they are different sizes. If its a 2nd generation blazer they are thesame soze hoses, however they are known for deterioirating from the innside out and clog the heater core. Best off replaceing both at the same time!