After my recent collision with a deer I have had a loud noise coming from under the hood on the driver's side very near the front bumper. This noise starts as soon as the car is started and runs continuously while driving. After killing the car this noise continues until the battery dies. I have learned that is I toggle the ignition 3-8 times to where I engage the starter but don't actually start the car it will sometimes shut-off. I was told by a local volvo repair shop that it was an air pump which kept 'charged' air in the intake for when starting the car to improve cold start performance. The shop then informed me that volvo does not have a part number for this item, cost is unknown, and they are on back order from volvo for an unknown length of time.

Can anyone shed some light on this mystery part ie currect name, part number, used part sources etc.

all help is greatly appreciated