Hillbilly of Leisure
Oh yeah...my 3.6R did this last winter. I tried to go through a deep puddle of slush at the grocery store (in a pretty good dip. Slush was about 8 inches deep). The car got stuck, but to be fair we still have the stock tires on there and they are bald as all heck. When I would hit the gas, nothing would happen. No rev increase, no tire movement. Engine sounded like it was bogging down. My azz was still hanging out in the highway during the throttle struggle. T'was a bit stressful. After a minute or two it finally pulled out of the slush.Also, the computer system got a little wonky on that trip. Maybe because it was a pretty rough road. A couple of times the engine wouldn't even rev if I put on the gas in the drive. The car wouldn't move. But it resolved eventually every time.
The strange part is that I was trying to spin the tires while working the steering left to right to find purchase. Does this sortof match the conditions when it happened to you? I have a gut feeling that it's some sort of safety "feature" related to the AWD. Maybe it had all four brakes activated to eliminate spin? I remember getting out of the car after I parked and was cursing like a sailor.