My '96 850 a/c is acting strange. It blows cold, but then stops cooling when idling for a while or when in stop & go traffic. If I turn the car off and then restart it, it blows cold. Also, when it stopped cooling the other day on the interstate, I caught a whiff of an antifreeze smell (briefly). The a/c was replaced by the original owner about a year and a half ago.

Any ideas on what is causing this (electrical switch, maybe?)

Thanks

The only way I can think that the two can be related is that the cooling fan is not coming on. This will cause the compressor to cycle off because of the high pressure switch and then possibly causing enough pressure in the cooling system to blow steam through the radiator cap (which get weak or crack over time).
Otherwise the A/C problem could be because of increased clearance at compressor clutch. I believe this will require that you get as much voltage as possible to the clutch solenoid. If there is a thermal switch on your compressor, the recommended fix is to bypass it. There are relays and a lot of smoke and mirrors between the ON switch and the compressor. Check the charging voltage at the battery. If it charging at less than 14 volts look into it. I found a bad positive battery cable (factory installed) on mine that I discovered beccause the starter began to drag. I made an additional cable from 6 gauge marine cable and lugs and installed it parallel to the old cable. This fixed the starter problem and also fixed about 98% of my compressor disengaging problem. I plan to see if I can increase the size of the feed wire between the connector under the microprocessor to the compressor. This beats the $500 (wholesale) parts only bill to replace the compressor and dryer.

greetings,
had antifreeze burnt type smell in my 94 850turbo, i just did the evap last weekend and replaced the heater core (because of smell) the smell is now gone. after i examined it, it had some rust stains or some kind of stains on some of the coils, but i never seemed to be low on antifreeze , i wonder if plastic and metal parts didnt co exist well and caused pinhole leak and caused smell? dont know but its cured now good luck,
frankd
south fl

My symptoms are the same. The compressor keeps cutting in and out, and needs to be replaced. Take it in first and make sure its not just a low level of freon, if they find its the compressor, look for a used one as new ones cost a grand cdn from volvo

The A/C problem and the anti-freeze smell are probably not related; the systems are separate. Is the car overheating? (That is, does the engine temp gauge exceed the 1/2 mark?) Are you losing coolant, judged by the overflow tank level going down?

Your A/C problem sounds like the classic low freon problem. If the system was replaced only 18 months ago (probably due to evaporator leak), it should be OK, but a recharge may be in order. Worse case, the evaporator is leaking again!

Gerald C