Heater problems, need some input

[ryanmcb]

Heater wasn't working in the 87. I replaced the thermostat and now it seems to be putting out nice warm air on defrost and floor. As soon as I switch to vent, it blows cold. I did it about 20 times because I thought I was going crazy. Why would it blow hot on the two settings and then cold on the vent setting? Any suggestions. I did notice that my cold-to-hot adjustment is really stiff on the cold end, that is new. Maybe a new cable?

Just for additional info. I can here a flap closing shut when I get about 1/2 way with the hot-to-cold lever.

thanks for your help