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Discussion Starter · #1 ·
I've had my 13' ST since new, coming up on 100K miles, and recently I've started hearing a high pitched wine/squeal which seems to be coming from the passenger side of the engine compartment. What baffles me about it is that it does not change pitch regardless of engine speed or vehicle speed. However, it only seems to come up around and above 2K rpms. It only makes this noise about 2/3 of the time. It will make the noise if I rev the car up above 2K rpms and hold it. I've reasoned that it likely isn't mechanical, like a bearing, pulley etc. Nor is it a bad transistor, ground, alternator etc. since those would change pitch with engine speed (I turned off the radio and HVAC system which made no difference to the sound). Maybe its a vaccum leak, PCV or ruptured BOV diaphram? I haven't noticed any other issues like low boost/power, so I'm frankly at a loss for what this sound is and its driving me crazy. I would like to at least have some idea on what this is prior to taking it into a shop, so anyone's help or suggestions would be appreciated.
 

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Discussion Starter · #3 ·
Have you checked the belt tensioner? The bearing goes bad on them
I've been worrying it might be something like that. Plus the apparent origin of the sound might support that. It there a particular way that I can check it? I've been planning to replace the belts soon anyway, so do I just check for play and smoothness of rotation in the tensioner pulley when replacing them?
 

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I've been worrying it might be something like that. Plus the apparent origin of the sound might support that. It there a particular way that I can check it? I've been planning to replace the belts soon anyway, so do I just check for play and smoothness of rotation in the tensioner pulley when replacing them?
Yeah see if there's any play in it. I would bet that's what it is
 

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Discussion Starter · #6 ·
Thanks for the suggestion. I will try and check that tonight. Does anyone happen to know if there's enough space there to remove/replace the pulley wheel/bearing?
 

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There's room to remove the pulleys. The one on the top spring loaded and you just need a 15 mm wrench to push toward the motor to release the tension off the belt.

20170112_165150.jpg
 

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Sound Sympathizer maybe??
Not to troll you too hard, but I believe the word you were looking for is Sound Symposer. Sorry for not being more sympathetic:crazy:
 

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Discussion Starter · #10 ·
Replaced both the pulley wheels and the belt (was already planning to replace the belt since I'm at 98K miles) and haven't heard it since. That being said, I hadn't heard it for about a week prior to doing this work, but there was a slight amount of play in the upper one. I figured I might as well replace them while I was replacing the belt anyway. Hopefully that solves this permanently.
 

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Replaced both the pulley wheels and the belt (was already planning to replace the belt since I'm at 98K miles) and haven't heard it since. That being said, I hadn't heard it for about a week prior to doing this work, but there was a slight amount of play in the upper one. I figured I might as well replace them while I was replacing the belt anyway. Hopefully that solves this permanently.
There was nothing to solve, you have tinnitus, it's in remission.
 
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