I just got the AC recharged and it certainly works fine. But after 10 mins or so, I smell a mildew type smell and it gets warm. If I turn it off for 5 mins and start it again its cold. So I assume some kind of switch or something is over-heating. My mechanic did say the evaporator is leaking, would this cause this?

I went with intermittent A/C for a couple of years. First I had the Evap. replaced. It held a recharge shorter and shorter until not at all.

Then it kept going warm if I excellerated out of a stop or it just got too warm.

It was the clutch in the compressor that was the problem. I didn't do what Steve recommended but that probably would have worked. I had the whole compressor replaced for around $700.

I finally have full time A.C again. I hope I get a few more years out of it.
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'95 854T 135,000

Sound as though the compressor clutch is the culprit. I had this problem last year. The compressor clutch is magneticcaly? drawn to the compressor when it is called for to come on. The pull gets weaker as it gets older and slips/ heats up. There are some shims on the compressor shaft between the clutch and the compressor wheel to create a gap. You need to make the gap smaller to compensate for the weaker pull.
I had researched this on this site ( do an archive search) and was led to believe that there would be 2 shims of different sizes,I pulled the clucth off of mine and there were 3. I took out the 2 thin ones and left in the thick one. I forget the thickness dimesions but it is very small.
This requires the compressor to be unbolted and pulled out of its resting place without disconnecting the freon hoses. This can be done with alot of swearing and effort. You will see 3 threaded holes in the clutch plate /wheel assembly. Thread 3 screws in to these holes to force it off of the compressor shaft and look for the shims.I think that they stuck to one side or the other.
( I do not remeber the thread size of the threaded holes, other than they were small machine thread, sorry!)

Put it all back together and has worked fine ever since!!


steve d.

'94. 850, 123k, '95. 855, 165K, '00. c70, 88k

Its gone into the shop yesterday and will know in about a week as to what the problem is. I wish I had the time and courage to fix it myself, but will see how it turns out.

You can have someone with pressure gauge check. But most likely the AC compressor clutch is the problem. If you had evap leak then you wouldn't get even those few minutes.

Hmmm. My 93 does the same exact thing. I've noticed that when the Ac goes warm the Ac clutch disengages which leads me to believe that it's low on refigerent since this is the defalut mode to keep the compressor from getting ruined.

I think there is a relay that could be acting up, overheating and shutting the system down.

I would double check the pressure in the system too, also the drain tube for condensate (water) and also check to see if your air intake in the cowl is clear. Remove a few screws on the pass side (where cabin air filter is). Hopefully you have a cabin filter, otherwise, get a kit from a dealer or online. it keeps leaves and debris off the evaporator, which is below, down near the floor level.

just a few thoughts on it.

I will look at the cabin filter. After driving it more today, it seems it doesn't cut out until I accelerate hard, above 2500 rpm. I suspect something is overheating. I was sitting in traffic for a go 15 mins, moving slowly and it ran the entire time, so I think its not time, but temperature of a part thats making it turn off. I will bring these up with my mechanic and see what he says. I don't care if I have to recharge the system every spring because the the evaporator is leaking, but I want it to work properly.

Sounds like it's low on refrigerant.

Thats the thing, I had it recharged, and when it does run cold, its very cold. But after a hard acceleration, the compressor turns off. So I am thinking that it has to be a relay, or maybe even the clutch. If the leak was bad enough I don't think it would cool at all. It seems the AC system in these cars is the achilies tendon. Thankfully I am not the only person with a problem like this as well. And hopefully the fix doesn't involve the dashboard coming out.

Forgive me, I think its the Condenser leaking, not the evaporator.

Don't forget the clutch on the compressor will open when you are Wide Open Throttle. Does the A/C come back on after a WOT?
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Tek