This last Friday night I took my car to get an alarm install in my 95 SSEI.
After they install the alarm I notice that the middle air vent wasn't workig any more.
The funny thing is, the top vent n bottom ones are working. Now get this they still work when i but only the middle vent to work. I took it back to the guys they looked around to see if a vent got lose. They said every hting looked fine.




PLEASE SOME ONE HELP ITS COLD IN NYC :(

THANKS TO ALL

Start by looking around under the hood for a hissing sound on the firewall. If the vacuum supply becomes disconnected then the HVAC programmer can't change the output vents. There are tubes that come from the throttle body and go to a vacuum tank on the firewall, before they go into the HVAC programmer.

Can you switch between defrost and lower vents?

Also check below and to the left of the glove compartment. Remove the passenger hush panel, and check to see that all of them are hooked up in there. There'* a round 'puck' with a bunch of vacuum lines. If they were rooting around in your dash, they could have messed something up.

Thanks for your help guy'* im going to try what you said this weekend.
and
no I cant switch between defrost and lower vents.
There both on at the same time




thankz again talk to you soon

That'* the default setting when the system has lost vacuum. Sounds like the alarm guys did knock something off, or forget to reconnect something afterwards.

Hey guys tryed some of what ya told me cant get it to work now im getting mad, others things are bugging out in the car

What other things are bugging out? Let'* see if we can find a common factor.

I have a exhaust smell when im going around 90 mph.
Also I feel heat at any speed and the heater control is off.
Please help and thanks

Jeez... assuming you're facing the right way around at the time, I cannot imagine how you would be smelling exhaust at that speed...

I think they've drilled (or opened up) a big hole in the firewall somewhere, maybe to pass some wires through, and air from the engine compartment is getting into the car. Sounds like some real hamfisted installers were working on your car, unfortunately...

I smell it inside the car strong