My buddy and i flushed out the heater core and some black liquid came out, now i got great heat. But it still smell likes antifreeze only when i first turn the heat on and goes away a minute or two later.

Also, why is it when the ventilation control (the **** that controls vents) is on the engine runs weird...like its bog down. I did find when i took it apart the BLACK vacuum line has continuous suction. Then loses suction as you give it gas. I know too many problems at once. Thank you in advance for your help.

Brian

 

This indicates that you have a problem with your vacuum system on your truck. You likely have a leak somewhere. If the vacuum goes away when you rev the engine, then the vacuum reservoir is likely not connected to the system. The location of which depends on what year you are driving.