AC blowing cool only on the passenger side, warm on drivers. Cadillac DeVille.

flomaster

I know this is an electric actuator door issue in the dash somewhere, the question is: are there (2) actuators one for each side? If so, where about are they located in the dash. I have been told that estimated hours from a independent shop is 2.5 hours, which sounds reasonable, but I feel that I can handle this work as long as it not too deep and buried in the dash that actually requires it to be mostly removed. I understand the part(s), the actuators are only about $60 bucks each from Amazon.

palsonl

I do have the same problem that AC is not coming out in Center Vent.
Please send me a link on how to remove the dash or panel to replace the actuators. Also, I appreciate if you would give me the complete part name for actuators. Thanks a lot.

broy42

I have the same problem on my 2004 Deville. Plenty of air flow both sides. the freeon level shows in the middle of green but I added more freeon and it seemed to fix the problem.My question is what regulates the cooling on each side (I can make passenger side cooler or warmer)? Does anyone know how the system works?

thecardoc3

broy42 said:

My question is what regulates the cooling on each side (I can make passenger side cooler or warmer)? Does anyone know how the system works?

When you have a dual zone system there are temperature blend doors that control just how much of the air that has gone through the evaporator core (cooling it) then goes through the heater core adjusting the temperature back to the desired setting.

One of the typical causes of the passengers side being colder than the drivers side where recharging the AC fixes it on similar GM cars can be found in understanding how the refrigerant flows through the evaporator core. For AC to pick up heat the refigerant has to change state from a liquid to a gas. Liquids of course are heavier than gas so when the refrigerant is undercharged most of the liquid refrigerant in the system boils off in the lower half of the evaporator core which primarily feeds air to the passengers side of the car. The upper half of the core starved for liquid refrigerant then doesn't cool the air the same as the lower half so the drivers side is warmer.

imidazol97

I'd like to add one point. I'm just a home mechanic...

I was active in reading forums about the related H-body Buicks and Pontiacs from 1998 through 2005. I owned leSabres from 1993 to 2015. After 2000 the AC systems were sensitive to a low charge. But, in my opinion, this is an an example where adding your freon yourself based on the cursory meters and indicators on over-the-counter freons often was short lived success.

The best thing to do, because the systems are so critical about having exactly the right amount of freon to work under all varying conditions, is to take it a good professional and have it evacuated and refilled with exactly the correct amount.

As long as you don't feel the system may have a definite leak, it took 14 years to change slightly. So get it back to the exact balances and hopefully it will go for several more years.