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Ecotec 2.2 Supercharged belt/pulley noise - YouTube

Car is a 2008 2.2 with 3.1" pulley, supercharged.

I've had this noise almost constant for about 2 weeks now. Its not the tensioner pulley (put a new one on thinking it was that, and cause I had to anyways), and I tried a second tensioner shock thing and no difference. I flipped the belt and it made no difference. I can't even fit a new oem belt on because its too tight (have any other 2.2 sc people found this to be the case?)

In the video I push on the tensioner bracket and you can hear it go away. That makes me think its a pulley somewhere near the top of the motor. I did some searching and apparently the snout bearings can go bad in the supercharger, but I haven't seen any videos showing the noise. I know the couplers go, but this doesn't really sound like a couple (marbles in a can or whatever the popular descriptions are). I used a mechanics stethoscope to try and pinpoint where its coming from, but I can't. They all sound normal enough.

Has anyone seen this before? I posted this on .net but people over there aren't too helpful I find...
 

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That looks pretty annoying and you need to cure that before it causes you real hardship. Not easy to tell from the video but definitely a dry bearing. something ran out of lubricant.

---------- Post added at 06:57 PM ---------- Previous post was at 06:45 PM ----------

This is not factory is it?
 

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Yea it's embarrassing. Driving a car from work now until its resolved.

Got the new oem belt on and it's still there. I spun the pullies while the belt was off and the tensioner is ok cause its new, the idler sounds ok too, and the supercharger feels good too (no excessive play or weird noises). I spun the alternator and I think it might be the bearings in it that are going.
 

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Stethoscope should pick-it up though!!! Now that you mention it, it does sound like a bad alternator bearing. The sqealing pig sound.
 

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Ya when the car is running you can't put the stethoscope on the bolt for the alternator pulley because it too is spinning, so all you get is the sound of the stethoscope rubbing the bolt. I stead I put it on the alternator casing as close to the pulley as possible and I couldn't hear the exact noise, but when spinning it by hand with the belt off, you can hear a bit of a clicking sound which might be it (since the other pulleys don't make such a noise.

The weirdest thing is that the only place I can really hear the noise with the stethoscope is where my map sensor is. It is an LSJ map sensor and it is held firmly in place with a piece of metal and the screw on the manifold. It has zero play, but when I put the stethoscope on the metal piece I can hear the whining noise more than anywhere else. Its not coming from there though, so it must be sound reverberating in that area (since its most certainly pulley related given what I've mentioned so far).

I'll try an alternator and see where that takes me...
 
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