I'm having an AC problem in my 2001 v70. My AC blows ice cold when I first turn on my car. It works well for 10 to 15 minutes, and then starts blowing warm. It's not a gradual warming either, there's a definite switch over to warm air. If I turn the AC off for about 5 minutes or so, it will work again when I turn it back on. If I leave it on, though it won't ever come back on its own.

I was at the Tires Plus getting a tire repaired and asked the mechanic there about it, he said it sounded like an accumulator/dryer problem... he told me there's a particulate filter in there that's probably getting plugged up, and that turning the car or ac off allows the sludge to fall off the filter and settle at the bottom... This explanation seems to make sense, but I've also been told it could be a sticking expansion valve from some of my more mechanically inclined friends.

Anyone here experience a similar problem, or know of a way I can diagnose either of these possibilities?

 

I will bet the compressor needs to be reshimmed.
When it blows warm check for power at the compressor. If you have power and the clutch is not on and turning the center section it needs to be reshimmed.

 

The compressor clutch was actually the first thing I checked... The compressor and clutch do seem to be spinning just fine, even when it's blowing warm. In fact it cycles through engaged and disengaged just as it does when it's blowing cold.

 

OK on to the next has anyone checked the A/C codes yet?
Also when it seems to blow warm does the air flow drop out of the vents?

 

It's not throwing any codes either, and no the air flow does not drop off, the blower stays going.

 

Ok then if the air flow stays exactly the same than that eliminates the system freezing due to a bad evap temp sensor.

Have you checked the high and low pressures?

 

Because my ac compressor had run with this problem for several months, it was worn down enough where the two shims sits, that I could just remove one. With only one shim it now has the right gap between clutch and compressor and works perfect. Rented a compressor clutch puller from Schucks (for free) and used my own metric 5mm and 6mm bolts with it, and the job was a breeze! Thanks Tech for a great tip! ...saved me a lot of money.

 

No, I think I can bring it to Advance to get it checked... my roommate works there, and he mentioned we should do that as well. I suppose I should check it both when it is and isn't working.

 

Yes you should check the pressures.

 

Our 2002 S80 exhibits similar problems. On a hot day, the air conditioner blows cold for 10-15 minutes, then there is an almost humid, warm air that flows. And if we just leave it on it continues to blow warm. But turn the air conditioning off for 5 minutes and then back on and "walla" ice cold for another 10-15 minutes.

If it is a relatively mild day (65-80 degrees), the air conditioning will blow cool all day. However, I have observed that even on mild days, especially if I'm in a lot of stop and go traffic it will sometimes begin blowing warm.

I've had the system charged (after they removed the old freon and vacuumed the moisture) on two occasions. The 1st time (about a year ago) I though had solved the problem. But the hot temperatures also subsided so this year when the 95-105 degree days returned, so did the intermittent AC.

I suspect the clutch, but what I don't understand is that if the clutch is slipping, why doesn't at least occassionally reengage and start blowing cold after it blows warm. Like I said, once it blows warm, it never seems to blow cold again, unless I turn the AC switch to off, wait a bit, and then turn back on. Then, we're back to blowing cold, at least for a while.

Any thoughts, suggestions or comments appreciated. Thank you!

 

It does that because the clutch basically overheats.
When you shut it off the compressor and clutch cools off then is able to work again.

 

Had the same problem on 1998 V70 AWD. Service wanted to replace compressor. I researched on internet and gave a different garage a how to diagram and photo and they removed 2 shims to get the proper gap. Problem solved for 1.25 hours of labor and no parts.
Compressor has worked perfectly for 2 years.

 

jrouse and tech,

Many thanks for the responses. I believe I will follow the jrouse route and see if (armed with diagrams and pix) if I can find a local mechanic that will reshim the clutch. It is a task that may be beyond my comfort level (which ends at replacing bulbs :-))

Again thank you and I'll let you know when I have a solution.

 

In regard to the a/c problem, the owners manual specifically states not to use the recurculation button for more than 15 minutes. If you do leave it on for 15 minutes it automatically blows warm air. You can shut it off and wait and the cold air will return. To all you posters out there make sure you read you manual and follow this simple step before going any further. Worked like a charm for me and I thought I had serious problems..........