Factual error: When the airbag blows in Lloyd's limousine, it stays inflated - it should instantly deflate. (00:08:40)
Factual error: Harry's tongue gets stuck to the chairlift, and stays stuck, even though it's not cold enough to see anyone's breath, or for everyone to need their jackets zipped-up. (01:11:30 - 01:13:35)
Factual error: When Lloyd drops Mary off at the airport, he watches her leave and then hits a parked car, inflating the airbag. First, the Cadillac Brougham Lloyd is driving was never available with a driver-side airbag, and secondly airbags are not designed to inflate after such a low-speed impact.
Answer: This is a scene that was cut from the theatrical release of the film, but is present in the extended cut and some international DVD versions.