Air/heating venting problem

[SRGriffin]

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

[yogi_123rd]

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.

[SRGriffin]

Originally Posted by yogi_123rd

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!

[willowwolf76]

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.