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Discussion Starter · #1 ·
My wife said she heard a big noise and then steam spewed out of the engine bay for a few seconds. She drove home two miles anyway, and i, thinking it was radiator/engine coolant related, was sure she fried the engine. I looked under the hood and the top radiator hose had collapsed, so I assumed that had caused a pressure leak in the system. So I changed the hose and thermostat and everything seemed fine. There was no coolant loss.

About that same time she noticed that the AC wasn't working.

I had the AC recharged at the shop (he said it was low). Wife drove home and said it cooled beautifully. The next day (yesterday), maybe two minutes after starting the car (the engine was still cold) we had the same "event" that I think she had had a few weeks earlier: there was what sounded like a burst pipe (a loud pop and hissing) which lasted MAYBE 5 seconds. I quick lifted the hood, but could see no visible steam or leaks or oil sprayed anywhere, but the AC doesn't cool anymore. Compressor seems to run fine.

Is there some kind of additive I can put in the gas to solve this problem? Kidding! Is there a traditionally weak valve or fitting or hose or some i such that I should start with? Would love any advice on where to start. Thanks.
 

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Discussion Starter · #2 ·
Oh, and there was steam during this second event -- I just mean that by the time I opened the hood, I couldn't see steam or where it might be leaking from.
 

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I don't think the radiator cooling fan is doing it's job and the a/c system is over pressurizing to a point that the pressure relief valve at the back of the compressor is releasing refrigerant.

Could be the fuse, relays or fan motor itself.
 

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Discussion Starter · #4 ·
win k -- thanks, I wondered about that. you think it could overheat that fast? It had only been running a couple minutes and the car was cold. But i'll check the fuses.
 

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win k -- thanks, I wondered about that. you think it could overheat that fast? It had only been running a couple minutes and the car was cold. But i'll check the fuses.
The engine won't overheat that quickly, but the a/c system will surely over pressurize that fast. There's a high pressure switch built into the a/c system that should have shut the a/c compressor's clutch off first, but that does not seem to have occurred.
 

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I think win_k on the right train, but maybe the wrong track... I think you can run the engine for quite a while in the driveway before the fan kicks in and the A/C does fine. Also, if you were driving at speed, the fan would not be needed.

But, it does sound like the A/C clutch is not disconnecting and you are over pressurizing. The question is why it's not being told to disconnect before you hit the maximum allowable pressure (?)
 

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I think win_k on the right train, but maybe the wrong track... I think you can run the engine for quite a while in the driveway before the fan kicks in and the A/C does fine. Also, if you were driving at speed, the fan would not be needed.

But, it does sound like the A/C clutch is not disconnecting and you are over pressurizing. The question is why it's not being told to disconnect before you hit the maximum allowable pressure (?)
If you can run an a/c system without a fan for quite a while before it over pressurizes, you've either got a duff compressor or are seriously low on refrigerant.

If you've got a set of manifold gauges, try connecting the gauges, pop both fan relays out of the fuse box, start the car and turn on the a/c.

Be prepared to quickly reinstall the high speed fan relay!
 

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If you can run an a/c system without a fan for quite a while before it over pressurizes, you've either got a duff compressor or are seriously low on refrigerant.

If you've got a set of manifold gauges, try connecting the gauges, pop both fan relays out of the fuse box, start the car and turn on the a/c.

Be prepared to quickly reinstall the high speed fan relay!
Maybe my memory is foggy then. I will run a test later if I have time so that the OP knows roughly when the fan should start kicking on.
 

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Maybe my memory is foggy then. I will run a test later if I have time so that the OP knows roughly when the fan should start kicking on.
That'd be a great test! I've other cars that publish the various action pressures for the pressure switches, but I've not seen such for the SAABs.

Would be good data to have.
 
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