My 97 XJ Country (4x4 auto) developed a buzzy whine about a week ago.

When it happens:

• When I press the gas pedal
• In drive or in park
• Even in neutral
• Hot or cold

Sound quality:

• Buzzy and nasal
• Within the register of a typical man's voice (I can kinda plug my nose and make a nyeeeehhhhhh sound and it's pretty close)
• The pitch of the sound tracks the RPMs exactly, including rising with acceleration, falling with deceleration, and jumping with shifts

Where:

• It's coming from the engine bay
• Seems like it's near the block

So what's going on??

 

My first thought was RF interference. For example, driving with the radio tuned to AM. A buzz/whine follows the rpm. Some hear it, some dont.

Where in the engine bay does it sound like its coming from? Front , rear, sides? If its on the passenger side, does it sound like its coming from the ignition coil? Is the ground strap connected to the block and firewall? Is everything clean?

 

Kinda sounds like you're describing power steering pump cavitation.

 

Middle of the bay toward the driver's side.

The PS pump is in the right place I suppose but the noise doesn't seem like it has any relation to steering.

Here's a video I uploaded of the sound. I'm sitting in neutral with the parking brake on and wheels straight:

 

Could be the idler pulley bearing, I had to replace it on my 96 about a year ago.

 

I could hear what sounds like faint static (no buzz tho), that did not change with rpm. And what sounds like an electric fan spooling up. Whatever that was, it seemed to follow the rpm. Didnt sound like the exhaust, or the engine. Ive heard power steering pumps whine, but it didnt sound like that. What i was describing with the radio tuned to AM, thats not the sound, either. Whatever yours is doing, im not familiar with it. Try another video, under the hood. Point to exactly where it seems to be coming from, if you can. Might help. Hopefully.

 

Spray some water, NOT OIL or anything else, around the serp belts, water pump, pulleys. If it changes start thinking new serp belt, or accessory pulley.

 

Here's a better video. Doesn't seem to be coming from the serpentine area at all

 

Hmm thats a good one. Almost sounds like the alternator.

 

I have bad ears but I did hear a ticking, or what I can describe as a loose chain sound.