Vent Control Doesn't Work

[procharlie]

My TTA vent control isn't working. I can change from A/C to heat, defrost, etc, and the vent output doesn't change. I pulled the HVAC module out of dash and disconnected some of the vacuum lines by pulling off the small rubber connector on the left side, and with the engine running there was no vacuum. I didn't disconnect any vacuum lines from the round selector switch because I was afraid of breaking something.
I did remove/install the engine on this car a while ago, and also removed the EGR valve/control module (and plugged the EGR port at the intake manifold, and capped off the vacuum line that had led to the EGR controller). It's possible that I could have demated a vacuum line during some of this work, but I don't hear any vacuum leaks anywhere and the engine seems to run OK.
I have looked for a heater control vacuum routing diagram for this car, but haven't found one online. If anyone has the diagram I would really appreciate it because it would make it much easier for me to trace the lines and find out what is wrong.

 

[procharlie]

I found my problem. When I removed the EGR, I plugged the line going to it, but that line also had a T that was connected to the HVAC vacuum line. I reconnected that line and the vents now work.

 

[TTA855]

I don't know if this will help you, but it's all I've got to offer: when I switch between heat and vent, I hear a loud clunk. It sounds like a flapper valve is hanging up. My mechanic advised me to leave it alone until it fails, since he's afraid he could break something by taking it apart to fix it. But it may be that your flapper has failed and is no longer switching between heat and cold.
I have the factory service manual. Would that help you?