'97 Contour
2.5L V6, 5spd
118,000+ miles

As of late I've noticed a "humming" sound coming from the general direction of the passenger side of the engine compartment. This happens both when I'm using my vents/AC/heater or if I'm not. It's intermittent, but noticeable to say the least.

Any suggestions as to the culpret would be greatly appreciated.

John