* Alternator Bearing: This is the most common cause of a buzzing noise that increases with speed. A worn-out bearing in the alternator will create a high-pitched whine or buzz.
* Power Steering Pump Bearing: Similar to the alternator, a failing bearing in the power steering pump can produce a buzzing sound that increases with speed. You might also notice some power steering issues.
* Idler Pulley or Tensioner Pulley Bearing: These pulleys guide the serpentine belt. A worn bearing in either can make a buzzing or squeaking noise that changes with engine speed.
* Wheel Bearing (Less Likely): While wheel bearings typically make a rumbling or growling noise, a severely damaged one *could* produce a high-pitched buzz, especially if it's only affecting one side. However, this is less likely given the engine compartment location of the sound.
* Belt Issues (Less Likely): While a slipping belt often makes a squealing noise, a very worn or damaged belt *could* create a buzzing sound. However, this is usually accompanied by other symptoms like squealing at idle or under load.
What to do:
1. Check the Belt: Visually inspect the serpentine belt for cracks, fraying, or glazing. If it looks bad, replace it.
2. Listen Carefully: Try to pinpoint the exact location of the noise. This can help narrow down the possibilities.
3. Professional Inspection: Because this requires more than just a visual check, it's highly recommended to take your Saturn Vue to a qualified mechanic for diagnosis. They have the tools and experience to pinpoint the source of the buzzing and recommend the appropriate repair.
Ignoring the problem could lead to more serious damage and potentially dangerous situations (e.g., alternator failure leaving you stranded). Get it checked out soon.
