Oldsmobile/Buick Repair: Heat, electronic climate control, intake manifold gasket

Question
My wife had the intake manifold gasket replaced on her 1993 Buick regal 3.8 liter V6 engine.  Since then she can not get the heat to come out of the vents.  All she gets is the defrost to work.  We have been told that there could be a vacumm leak. I have worked on cars since I was 13 (I'm 45)so I know what a vacumm leak sounds like, but I can not find a vacumm leak. My wife called a Buick dealer and they said something about an electrical connection that controls the vent system. I was wondering if you could tell me were this connection is in the engine compartment.

Answer
Hello Brian,
I'm not sure that car uses vacuum to operate the air doors, but if it does, there will be a hose or plastic line from the intake manifold to a reservoir under the hood someplace, and then through the firewall.

If you have electronic climate control, the air control doors are operated by little electric motors.

If you have manual controls, there are cables from levers to the doors.

But check the heater hoses first, and see if they are getting hot. There could just be an air bubble trapped in there keeping coolant from flowing through the heater core. The heater hoses should get hot before the top radiator hose does, and then stay hot. Both of them.
When changing the manifold gaskets, the coolant was drained, and sometimes it needs burped, or checked and topped off several times to make sure all the air is purged from the system.

Of course if the defroster air is plenty hot, then you are back to air flow doors.

Have you talked to the shop that did the gaskets?

Van