Anyone have any suggestions on my wife's continuing problem with her '95 850 air conditioning. (189,000 miles and still kicking - mostly)

Last summer with the AC switch on, it would cycle back and forth between 10 minutes of cooling followed by 10 minutes of blowing hot air.

After the usual checks at the dealer, the found the core to be leaking and $1200 dollars later it worked.

This summer, the problem is occuring again with a slight twist. It will work the first time driving for the day, but future trips result in nothing but hot air. So far they've replaced both linear pressure and pressure cycling switch.

The other day we took it in while it was malfunctioning, they hooked up the diagnostic computer, and everything said it was working fine (except for the HOT air coming out of the vents!). The next day they tried duplicating it (and of course it didn't act up!).

Any ideas would be appreciated!

Ken