Hoping you guys could help me out with an HVAC issue. It seems that my HVAC system (and I really should say AC system here because I obviously haven't used the heat over the summer) is possessed. When I have it on full Auto, it seems to be opening/closing doors continuously and "farting/groaning" up a storm in the car. When the car is hot, and I set both temp dials to 68 on full auto (including the rear), the car MIGHT blow really cold air, but it also might blow kind of warm air for a while (it usually blows cold air, but every now and then it won't for some reason). It also just likes to continuously cycle the doors (don't know whether it's the blend doors or the recirc doors or what doors actually exist) and the strength of the blower fan.

I could perhaps see the temperature variation because I recharged the AC system myself earlier this summer. I put R-134 in until the pressures read about what I thought they should (car took about 22-24oz of R-134). Since this was a DIY job and the system wasn't properly evacuated and then refilled from empty, I can understand if the temp might not be exact and I will probably have a shop do it before too long.

However, the continuous cycling of the doors and blower speed has me worried. Does anybody have any suggestions as to what to look at? I recently had part of the dash apart so I blew compressed air over the temp sensor to the right side of the steering wheel in order to clean dust off of it. Don't think I screwed anything up there because it's been acting this way for a while before I did that.

The really weird thing is that even if I go to manual mode and set the fan speed myself, the car was still varying the blower speed (or maybe it was redirecting air to other zones so it felt like the speed dropped off). I guess I'll have to do some further testing and post more specifics.

 

The farting noise is a pretty easy fix, remove the upper glove box and reach into an almost impossible to see location and rub some grease on the plastic link for the recirc door. It worked great on my SE, once I figured out that the TSB is wrong when it says to turn the key off. Put the system is recirc And grease and then turn on fresh and try again (I don't recall which was the winner)

http://www.disco3.co.uk/gallery/albu...irculation.pdf

 

Thanks for that. Lubricating the recirculation linkage doesn't look too bad, so I think I'll give it a shot.

As to the rest, I went out today to make better observations and, of course, the AC performed flawlessly.