Buick Lesabre Blows Warm Air And A/C Switches Itself

A/C problem with my 1993 Buick Lesabre Limited.
Question = When I press on the "Auto" button to turn on the A/C, the Dual Climate Control system switches to "Econ" mode as well as the temperature on the display flashes for about 2 minutes after starting the car. Also, when I checked for codes on the climate control by holding the Off and Warm buttons together, I got "141" and "48". Before when the "auto" feature worked and the display didn't blink, the A/C worked fine and blew cold air.

I noticed that the A/C wasn't blowing enough cold air so freon was added. Three days later the A/C compressor continued to work in the "Auto" mode, but the air in the car started being warm. When I checked the freon in the system, the pressure was high and the compressor still worked, but the air was still warm and the refrigerant lines and condenser were warm. Since the pressure was high, I properly removed some freon from the system to lower the pressure.

Then when I added a bit more freon to get back to the normal pressure level in the system. The A/C compressor stopped working and the " Auto" mode is disabled. Also, I noticed that when I added freon, the lower part of the refrigerant line was cold, but the upper part of the line towards the condenser was warm, as if it was plugged and didn't want to recirculate.

I checked the compressor by adding a small amount of voltage to the A/C compressor relay, and the A/C compressor does work. It just doesn't automatically because now the "Auto" button is disabled, and it automatically switches to "Econ". Would it be possible that there might be a " clog " in the system not letting the freon recirculate? What is wrong with the A/C system?

buick lesabre

 


ANSWER:

You may have more than one problem.

First things first. Evacuate the freon and add the proper amount. If the amount removed was less than the correct amount, add dye and freon and check for leaks. You must start with the proper freon charge. With all the adding and removing you have been doing there is no telling how much is in there. Just getting the pressures right does not mean the correct amount is in the system.

After the charge is correct disconnect the battery to clear any codes in the controller and check the function. If charge was good to begin with, you might have a restricted orifice tube. This would give you the temperature of the tubes problem, the pressure problem and the warm vent temperature air. But you cannot determine this without knowing that you have the correct amount of freon in the system.

If the A/C system on your Buick is still switching to ECON by itself, you may have a faulty control head. That is the panel in dash. Have it replaced.


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