So...

late last year, the AC got to where it was kinda cool on the passenger side, and warm on the driver's side. Compressor was working, and the pressure was close to normal.

I charged it, but it never would act right. The gauge would kinda meander back and forth, but not go up and down as the compressor cycled like it should. After charging it, it worked a little better for a couple days, and then one day after coming home form work running the AC on the way home, and as soon as I shut the car off, I heard this kinda fart sound from under the dash on the driver's side, and the AC didn't work the next time I tried to use it.

So being winter, I didn't mess with it, but did do some reading and found that the inability of the system to balance itself is often caused by a faulty expansion valve. A month ago, I replaced the expansion valve and drier, and found that it had blown an oring on the inside of the expansion valve. I took it to a local shop to have the system evacuated and filled, and that seemed to solve the problem, although it would still get cold faster on the passenger side than the driver's.

Today I drove it, and when I first left, everything seemed fine. After my last stop before heading home, the driver's side started blowing warm air, and the passenger's side was still cool. If I turn the dial to hot, it get's really hot, and turn it back, I can hear the mix door moving, and it cools back down.

I have tried to do the reset where you hold the Recirc, and defrost buttons at the same time, but all that does is turn the air on.

I am guessing I need to go ahead and replace the compressor and the evaporator, but I am open to suggestions if anyone has any ideas.

Thanks!

 

To add to the mystery,

I just went and took it for a cruise down the interstate. At highway speeds, the passenger side is really cold, the driver's side is half ***. When I slow down to get off the interstate, the temp then drops on the driver's side to almost as cold as the passenger. Get up some RPM's, it stops cooling on the driver's side.

 

Can you cycle through all climate control modes with the a/c turned off, and there is correct function? It will be easier to check this if the temperature is turned all the way up and all the way down (two tests).

This will help diagnose if you have a mode (blend) door problem or blend door servo problem. If you are getting cold at all, and you are 100% absolutely certain you have sufficient refrigerant, the blend door is the next diagnostic step. It doesn't sound to me like you are 100% absolutely certain that your refrigerant is full.

 

Thanks for the reply...

I was thinking of taking it to the shop and having them run the black light over it and see if they can see any leaks now. They put dye in it when they refilled it. At this moment, I don't know that it has enough refrigerant. Like I said, the passenger side is really cold, and when we fist had it charged after I changed those parts, it was working great. So it is possible there is a leak that would explain the declining performance.

I also noticed tonight when I was messing with that the compressor seems louder than normal, and when I shut the car off, I am hearing a lot of noise in the coolant lines if that means anything.

I loaned my MBII scanner to my kid and probably won't get it back for a few days. I believe it will do real time data on any system on the car.

 

I had a very similar problem on my 2011 GL and took it to two places......both said it was a weak compressor. I bit the bullet and replaced compressor myself about 2 months ago, and havent had a problem since.....its blowing 40 degree air both passenger and driver's side. Was quoted about $2600 at a shop to do the compressor, drier, and evaporator......I wound up just changing the compressor myself for $500.

 

So I wanted to give some closure to this topic.

I took it back to the shop that charged the AC after I did the work. The guy called me after I dropped it off, this was after telling me they would inspect it for free, and told me there would be a .$24.99 charge to do the inspection like I was trying to get over on them or something. I finally told him I wasn't going to argue about 25 bucks, go ahead.

So a couple hours later he calls me and said it was ready, but that they weren't going to charge me the inspection fee. Hmmm.

I get there, and he said that the system was low by almost a pound, and they recharged it, checked everything for leaks except the condenser core, and couldn't find any leaks. That was on memorial day, and it has worked perfectly since then, and is actually a little colder on the DS than the PS vents, and it's all much cooler than it was the first time they did it.

I think they screwed up when they charged it the first time and somehow didn't put enough refrigerant in it. Every time I would turn the AC off, I could hear gurgling in the lines like there was air in them. Since they redid it, no noise from the lines at all.

 

Glad you got it solved. Curious, in case I need to follow some of your steps, How much was the expansion valve and drier? Are you satisfied that those 2 items were the root of your problem and lack of proper charging by the shop was just a follow on issue? How much were you charged to evacuate and fill the system? How difficult was the job of replacing the expansion valve and drier? Thanks appreciate your sharing

 

I am pretty certain at this point that the expansion valve was the original issue. Now, almost two weeks after the second evacuation and recharge, it will freeze your face off with the temp on low running down the highway.

The expansion valve and drier were 80 bucks, and it took about 4 hours to replace both. The biggest problem I ran into was getting the bolts lined up to tighten the Expansion valve back down. It's got a bracket that goes around one of the lines, so it kinda floats. I used a pick to get it lined up on one of the holes while starting the bolt in the other. I did the drier without removing the front bumper which saved a couple hours of work.

The first time they charged it, when I called to check on it, they said it was ready, and when I got there, they said the tech had to "cycle" it again because he didn't think it was right the first time. When 'I picked it up the first time,the rear air was not on. The day it started going warm again, I had reached in the back floorboard to grab something and turned the rear AC on by accident. When I picked it up the second time, the rear air was on full blast. I think what happened when they recharged it the first time is they didn't run the rear air. I am not sure cause AC is not something I typically work on in any of my cars, but I would assume that if the rear air wasn't on, the lines wouldn't be completely purged.

I bought the ACM/Fujikoki expansion valve $38.00, and the denso receiver/drier $39.00 at parts geek.

Good luck.

 

Thanks for that tip. Yah, ran into the same annoyance with that bracket. Stuck a bamboo barbeque skewer into the lower hole to get them to align.