With the engine running at idle I discovered my 1999 626LX's air conditioning didn't shut off even when the "AC" button was pushed and the green light extinguished. Just before discovering this however, I'd observed smoke coming from under the hood, soon followed by a sudden violent gaseous discharge from the right side of the engine compartment which lasted about 10 - 15 seconds before it suddenly stopped. Thinking I'd perhaps blown a radiator hose or something I looked under the car but saw nothing - no indications of coolant or other leakage at all. No visible mess under the hood either. That's what led me to discover the AC situation, and I suspect that the violent discharge was the accumulator relief valve maybe relieving an air conditioning system over-pressure or thermal over-temp condition (?). Anybody out there familiar enough with this kind of event to know what's going on here? I can't see anything obvious yet.