View Full Version : AC Trouble...

07-01-10, 04:41 AM
Ok, has anyone had this problem and if so, what was your cause and solution? Assuming I do not need a freon charge (I really don't) when I run under a load, my AC blows through the heater vents instead of the dash AC vents. When the car's load decreases, or it is in a cruising state, the AC works through the Correct vents. I also have trouble with it (AC) warming up after a while and I turn it off for a few minutes and it will blow cold again.

07-01-10, 11:40 PM
Would be nice to know what year and model??? 1957 or 1997? Most times on any car with this issue, its a vacuum hose leaking, split, pinched etc. Add the car info to your profile so we never ask again.

07-02-10, 03:31 AM
I'm sorry. It's a 1991 Cadillac Brougham. I thought it was in my profile. I guess I need to go redo it. And yes, I was thinking vacuum also but was wondering if anyone had the same symptoms that would help me narrow down where to look based on their discoveries.

07-02-10, 09:42 AM
I think the air is directed mechanically by rods that divert the air to the defrost/vents/or floor. and is controlled be the climate control display under the radio.

07-02-10, 01:24 PM
Add the info into your signature. Start at the engine with hoses at the intake manifold and trace each one to the firewall.

07-02-10, 01:31 PM
I had the same problem with my car (307 equipped). On the 307 Brougham, on the passenger side firewall, is a black plastic ball with a small vacuum line coming out of the center. In my case, the hose was hooked up, which is why the AC worked at idle, but the line was split and was leaking. I'm sure the Brougham's with the Chevrolet engines have a similar set up.

07-07-10, 06:52 PM
I checked that vacuum hose that connects to the plastic ball on the passenger side, but the hose was all good. I had forgot that I already replaced it about 6 months ago.

Any other ideas possibly?..I did notice though that the hose from the ball to the driver side where it connects to an electronic component which is partly made of plastic and rubber...it seems as though the rubber part of that component is a bit old and cracked when bent...could that component be a factor?..its placed on top of the driver side valve cover next to the hot air tube for the TAC.

Today though when I was driving I did notice that it didn't switch completely to the bottom vents, but for some time the door which directs the air was half way, in which the cold air was coming out both from the normal face air vents and bottom vents at the same time..