There isn't really sufficient information to base a diagnosis upon. The national car repair shop that you took the car to should have vacuumed the A/C system down and checked to make sure that it was sealed up well enough to hold a vacuum before they put R-134 in it. I think that if it is leaking oil, then it is going to be leaking refrigerant (R-134). In a car air conditioning system, the oil is carried around by the refrigerant, and if the relatively dense and thick oil can get past a seal, you can bet the refrigerant gas can get by it much more easily. So, if it is leaking oil, then they should have told you that it is leaking refrigerant too.

Actually, thinking about what you wrote, and what I said, above, I think the place you are dealing with is either trying to rip you off, or they are incompetent idiots. Or both. Be especially suspicious if they are trying to sell you lots of work on your A/C system, like maybe trying to get you to buy a new compressor from them. I don't know any A/C shops in Phoenix, but have you tried the Volvo dealer? I know that we sometimes get down on the dealers for their outrageous prices for parts, but at least the one here in Ocala, Florida is honest and knows what they are doing. The one in Phoenix can probably diagnose the problem accurately and honestly for a small price.

If your compressor is really leaking oil (remember: the place that told you this might be dishonest or stupid), then you may need either a new compressor or to have yours rebuilt. But find an honest and competent shop and get a good diagnosis first.

BTW, do you know anything about A/C work? There are some things that are different from basic car work, like when you fix a leak you MUST vacuum all the air out of the system before you recharge it.

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Scott Cook - 1991 745T, 1985 RX-7 GSL-SE, 1986 Toyota Tercel (Don't laugh, it is reliable, faithful AND gets 41 mpg!)