Tensioner Pulley Bounce
 

I hear some noise under the hood when I accelerate. It's like a faint whirring/chirp.

Can't really tell where it's coming from if I look under the hood. It happens when driving as well as when I rev the engine in neutral.

Looking at it I can't tell where the noise is coming from, but I do see the tensioner pulley bouncing around. Is this bad? Could it be the cause?

How many miles do you have?

78,000 on a 2006.

The auto-tensioner pulley shouldn't be bouncing around at idle when you're looking at it.
Check the drive belt to make sure the tension is within spec. The owner's manual has the information on how to do this. Also consider having someone in the car rev the engine in park or Neutral (hand brake applied) while you try to isolate the sound under the hood.

Thanks PAC.

Had someone rev it and still couldn't isolate the sound. It's really faint in the cabin but it's high pitched so it drives me crazy. I'm going to just order a new tensioner and belt I think.

I'm just wondering if perhaps that will fix it or if it's the water pump? It sounds kind of like the loud fuel pump on my civic back in the day.

Hey, I uploaded a video with the sound...can hear the whine the best at about 12 seconds on. It's hard to hear but it's there if you strain

Thanks for checking it out - appreciate the help.

<iframe width="425" height="349" src="http://www.youtube.com/embed/6vXlnrh1-zw?hl=en&fs=1" frameborder="0" allowfullscreen></iframe>

Tried to edit the previous post, couldn't figure it out... here is a working link.

http://www.youtube.com/watch?v=6vXlnrh1-zw

Video of the pulley bounce. Of course when I go to film it it's being pretty tame, but it was bouncing quite a bit more the other day.

http://www.youtube.com/watch?v=VjaRMuzUas0

If I picked the right sound out of your video, then it is very close to what I'm having right now. If it it the case, then here are some bad news: the sound is still there even in case driving belt is out (you can easily test it), so I assume it is either transmission, or timing chain related.

Karlo, mine makes the noise even in neutral and it does sound like it's coming from the drive belt side of the engine.

I'll try this weekend to take the drive belt off.

Mine is the same: RPM dependent noise even in neutral and park. Chain is the same side, under the cover

guys have you had a valve adjustment yet might be worth haven done plus you can examine the chain at the same time.