Unfortunately for you, it's not in print anywhere in any of Volvos literature and due to obvious possible legalities, I'm sure it never will be. I heard about it verbally. You'll also fail at getting anyone from Volvo, including reps or dealer management, writers to admit to knowing anything about this.

So, I can't tell you how to proceed legally but it's now up to people at this board with S80s who note this and techs in the field who hopefully know about it, if they're concerned and care, to do what little we can when we see a car that's not been modified, as I mentioned earlier to correct this with individual cars.

My 2 step easy fix, takes a minute or two:

1) From under front of car, cut access tubing with hack saw blade, blade only as it helps get access close to the air guide, so that it's flush with air guide.

2) Open hood and take one long plastic tie strap and tie the tube to the large wiring harness in front of it.

Once these 2 steps are done, I highly doubt that it can come loose and ever be a problem.