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Turbo Chirp/Whine when Spooling Down

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Old 07-22-2024, 11:52 PM
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Default Turbo Chirp/Whine when Spooling Down

Hi All,

I posted about this in my build thread but figured I'd get more traction if I made a separate post.

The turbo is a genuine Garrett 2560R. I did buy it used, but it was new in 2019 (?) or thereabouts.
Previously, I had another 2560R that made this same sound, but recently died. I have no idea how old that turbo was, but given my turbo kit was ~20 years old, it could be the original.

Mostly I'm wondering if anyone hears a similar noise from theirs, and if I should be concerned about it. I don't hear it all the time, but it is often audible from the cabin when coming to a stop.
Thoughts? Prayers?
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Old 07-23-2024, 07:52 AM
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That’s odd, I never noticed that noise whenever the turbo was on my car prior to selling it to you. If you end up having any problems with the turbo let me know and we can work something out.

Personally I think it sounds almost like a blow off valve whistling. When I was adjusting the spring pressure on mine a while ago, some settings would cause it to whistle under certain conditions. Does unplugging the manifold reference line on your BOV make any difference?
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Old 07-23-2024, 10:51 AM
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Hey Watterson, I appreciate that! I have no concerns over the health of the turbo when you sold it to me. I checked the shaft play when I received it and it felt great. Again, I appreciate you hooking that up.

Mostly, I want to see what this is so that I don't kill another turbo. Like I said, my old turbo made this noise too, so I suspect it's another part of the system, or (hopefully not) something like an oiling issue.

The BOV is a good point. I'll see if I can get around to that today or tomorrow. I'd be stoked to find out that's all it is.
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Old 07-23-2024, 01:38 PM
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FWIW, about the only time I hear my GT2560R is after I shut off the engine in my garage. If the neighborhood is quiet, I can hear it slowing to a stop over 10-15 seconds. Don't quote me on the time, that's from idle and I haven't paid attention lately. Closing the garage door creates enough noise to drown it out. Mine also doesn't whine much, if at all under boost (18 psi) but I'm guessing the intake setup makes a difference. I'm running the FM airbox with their hush kit (lid and foam) with some extra foam in the fender and where I saw any gaps.
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Old 07-23-2024, 01:59 PM
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See if it makes the same noise without the intake on.

I had some weird noises from one of my old intakes, it made some bizarre resonate frequencies revving and spooling down with the intake on, but nothing with it off.
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Old 07-23-2024, 02:08 PM
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I will put removing the intake on the list of things to try. FWIW I had a different intake setup on my old turbo (different filter and elbow), but it wasn't dramatically different.

I do hear the turbo spooling down, but that's also in the garage and I usually pop the hood to let the heat out once it's parked in there.
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Old 08-06-2024, 11:36 PM
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Originally Posted by Watterson02
That’s odd, I never noticed that noise whenever the turbo was on my car prior to selling it to you. If you end up having any problems with the turbo let me know and we can work something out.

Personally I think it sounds almost like a blow off valve whistling. When I was adjusting the spring pressure on mine a while ago, some settings would cause it to whistle under certain conditions. Does unplugging the manifold reference line on your BOV make any difference?
Ding ding ding! We have a winner. I pulled the entire BOV off the car today to test this theory and see if my BOV was potentially leaking and causing power loss. The noise I originally posted about was gone immediately. I'm not sure that it was causing any issues, but I'm glad to know where it's coming from at least.
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