[dvl]

Good day folks,

Today I took my car in for servicing. They'll be fixing this as I type. While at the garage, and in a parking lot next to a busy road, the exact ideal conditions, I took some audio recordings of the sound. Why?

Because I knew you'd love to diagnose the issue.

I have two recordings.

The first is taken from the passenger side wheel well.

The second is taken from directly in front of the grill.

The winner get beer and/or chocolate the next time we meet.

 

[rasterman]

I can't say I recognize it, so I'm going more by what it doesn't sound like, and guessing after elimination... power steering pump.

 

[dvl]

Oh I should add:

* the sound frequency changes with engine speed.
* I do not hear it at higher speeds, but I suspect that is because it is drowned out

 

[Seabass]

Kind of hard to tell. I'll guess timing belt pulley starting to go.

 

[dvl]

Kind of hard to tell. I'll guess timing belt pulley starting to go.

FYI timing belt was replaced in August.

 

[rasterman]

FYI timing belt was replaced in August.

I think of timing pulleys (and alternators for that matter) having a higher frequency scree to them, largely why I went with the ps pump.

 

[tdelker]

Doesn't sound all that strange to me... Maybe something is wrong with my car

 

[Seabass]

I'm digging. I can't say I hear anything wrong in that audio. But I'm assuming that it's a noise that just recently showed up. My failing pulley was definitely high pitched. It sounded similar to an electric power steering pump.

 

[dvl]

I think the problem with audio is having no basis for comparison.

Here is the sound from the passenger wheel well post repair.

 

[tdelker]

Okay, it sounds better now I'm just going to say accessory belt. I can't think what else would sound like that but not be the ac or power steering.

 

[DavidPeab]

Once it was the pulley on my PS pump. http://www.subaruoutback.org/forums/66-problems-maintenance/47658-power-steering-pump-failing.html

Once it was my alternator. http://www.subaruoutback.org/forums/66-problems-maintenance/50092-alternator-rant.html#post480412

I replaced all the idlers and tension arm idler when I did my timing belt. Did you have those done?

 

[dvl]

Hmmm, I don't have the work sheet here, but in July, several (5 I think) pulleys were replaced.

 

[Seabass]

I think a recording of the engine revving could be helpful.

 

[dvl]

I also made this recording of the engine revving. It was too large to email. I just downloaded it off my phone.

 

[dvl]

Similarly, here is the recording from the driver's wheel well.

 

[tdelker]

When do we get the answer? The suspense is killing me

 

[dvl]

It was the alternator. The bearing were going, hence the noise.

I am grateful for that noise.

Mind you, I got another 7000 miles on that alternator since I had that overheating issue from the dead water pump / pulleys.

 

[tdelker]

Thanks!

On a side note, I noticed that the water pump is NOT toothed, so if it freezes it doesn't guarantee that the timing belt will break. Sounds like that is what happened to you, luckily!

Tom

 

[dvl]

Ahh sounds good. But can you figure out why the other pulleys died at the same time? How odd. And now another bearing...

 

[tdelker]

I can only guess that it was because of the overheating. Maybe...