1996 850R AC cycling causes noticeable jolt

[rhalkyard]

I finally ended up switching my 850R's AC on this weekend, for the first time since I bought the car nearly a year ago. To my surprise, it blows ice cold, but at steady highway speeds, there is a slight, but noticeable jolt every 20 seconds or so as the compressor cycles on and off. I gather that the cycling is normal, especially when it's not all that hot outside, but the jerkiness of it is somewhat off-putting.

On any other car that I've driven, all much less powerful than the 850R, compressor cycling was barely perceptible at highways speeds. In this case, though, it's harsh enough to actually be a bit annoying and the slight surging and bogging that comes with it makes it difficult to hold a constant road speed. Maybe I'm just being overly fussy, but I have a hard time believing that it's supposed to be like that.

Any pointers on what could cause harsh engagement/disengagement? It's almost as if the compressor's load on the engine is greater (or less) than it's supposed to be, and/or is not being properly compensated for (assuming that the ECU does something like that).

[abscate]

If you gave too much refrigerant in the system you will get this. Using the cans and cheap gauges on the cans is a quick way to overcharge the system.