Since I had no luck finding information on this and no one replied, I decided to share my experience, hoping it may help some of you out there.
Per VADIS, the A/C system should be recharged on the HIGH side. Finding this to be not only odd, but dangerous, I recharged my sytem on the low side (port is underneath the power steering reservoir). Per other posts I read, it's impossible to overcharge, since the DIY kits available at local parts stores do not allow for overcharging-they simply stop transfering refrigerant when the maximum system pressure is reached.
At first, I added one can, and the frequent cycling of the compressor stopped. However, the air did not feel very cold. System pressure was near 30 psi (when compressor was running). I decided to add a second can. However, while ading the refrigerant, my compressor disengaged, and started cycling, staying on for only a second or two at a time. After I got the second can in, I let it run for a while, and the compressor would only come on for a second or two at a time. Later that afternoon, when I wne to start the car, I got a bunch of smoke from under the hood. When I opened it, I could smell it was refrigerant. I was not able to determine where it was discharged from.
For the next couple of days, I had no cool air from the A/C. I went back and released as much air out of the low side port, without allowing any of the refrigerant to escape (only the air pressure). Now my A/C runs fine, and the compressor hardly cycles on and off (it consistently stays on).
From what I can tell, the system holds less pressure than what the dispensing cans allow, and the air needs to be let out of the system after a recharge. I guess I overcharged it and somehow there's a relief valve somewhere in the system. It is currently at about 32 psi. I hope this helps some of you out there coping with the remaining hot days without A/C.
99 S80 T6