1976 Heater/Defroster issues

[My daughter' Z]

Since winter is coming on I need to start figuring out what is wrong with the heating system in our 76 280Z 2+2. The fan switch works great, but the air will only blow out of the vents in the front of the dash, neither the defroster or floor vents will work. I have examined the switch linkages and everything seems to be hooked up properly and functions normally. The other issue I am having is that the air that does blow out does not seem to have any trace of heat in it no matter how warm the engine is. If anyone can help with either of these issues or point me to a thread I would appreciate it!

Gary

[sweet280zx]

Check and make sure you have vacumn coming from the engine into the heater controls. When you switch them around and turn them off you may here a little vacumn in dash. There should be one vacumn line going thru firewall into dash. Hope thi helps.