I have air only coming out of the defroster... yea, I know, a vacuum leak causing the vacuum selector not to work, the default... yada yada....

Nope. Yes, my '83 TA, my 87 Formula 350, yes, your camaro... all have that funky vacuum switch. Not my '87 TA with a digital dash:

2 electrical connectors, no vacuum lines.

Anyone have any idea where to look?

 

Are the HVAC doors vacuum controlled or do they have electric motors on them? Just wondering if it still could be a vacuum problem but you need to look elsewhere for the leak

 

https://www.thirdgen.org/forums/pict...822766&thumb=1
I found this in my shop manual for the Digital Dashes.

 

thanks, but that drawing can't be of the correct setup. Like you see in the picture that I posted, there are no vacuum lines going to the back of the controller like that drawing shows, and it shows a selector that uses a slider, where mine doesn't have that, but has push-buttons.

 

Yours is still vacuum controlled, there's a vaccum servo in there somewhere, prob right there. Follow the vacuum lines from the ac heater box back and see where they go. I'll look in my fsm and see if it helps.

 

Oops, I think I might be wrong about that, still not sure after checking out my 87 Factory service manual. The actual 87fsm doesn't mention the digital dash option at all, but the 87 electrical supplement describes the digital dash, but not the push button hvac. However, there is a diagram in the 87 fsm that doesn't seem to have a reference and isn't in my 86 fsm (sorry, don't have a 88). I think it shows the ELECTRIC actuators for the temp control that go with the push button hvac. There's probably electric actuators for the modes, too, but I don't seem to have that supplement.hth