Air/heating venting problem

Hello,

I have a 91 Buick LeSabre with a air/heating vent problem. When I turn on the heat or air I cannot get air flow out of the center vents in the dash. Air flow only comes out the top and bottom vents. I have checked the relays under the hood and they all seem to be operating. I bought a new relay and just subsituted it all the way down the row of realys but no change. Any ideas?

Steve

The valves for directing air out the vents in the dash are operated by vacumn. Look on the firewall under the hood near/under the vacumn assist module for the brakes. There is a vacumn accumulator mounted there with connections for two vacume lines. One line comes from the engine as the vacume's source. The other line will connect to the ac/heater unit thru the firewall. Your problem is most likely that one or both of these lines has fallen off and no vacume is getting to the ac/heater module.

The valves for directing air out the vents in the dash are operated by vacumn. Look on the firewall under the hood near/under the vacumn assist module for the brakes. There is a vacumn accumulator mounted there with connections for two vacume lines. One line comes from the engine as the vacume's source. The other line will connect to the ac/heater unit thru the firewall. Your problem is most likely that one or both of these lines has fallen off and no vacume is getting to the ac/heater module.

But.....but......but.....I could swear I looked at this! Thanks Yogi!

Hi, I have the same problem with my 97 Buick LeSabre. After taking it to the dealership, they said it was a problem with some computer chip. The part alone costs almost $1000 so I've just lived with the air coming out of the windshield and floor.

:banghead: