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Old 09-04-2018, 05:04 PM   #1
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Whirring sound from ~1700 RPM

Anyone have any idea what this noise might be? I'd describe it as 'whirring' and sounds like a belt idler or accessory bearing, but I've listened in the engine bay and doesn't seem to be coming from any of the obvious culprits like valvetrain, alternator, PS pump, etc. I can actually hear it best in the cabin, more noticeable in there than the engine bay. What's also interesting is that it's not there at idle, but kicks in at about 1700 RPM and then goes away again quite repeatably below that. Also disengaging the clutch has no effect, so definitely from the engine and nothing in the gearbox. Here's a video that will hopefully help. Any ideas of what to check? Thanks!

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Old 09-06-2018, 09:28 AM   #2
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I can't listen to the video as I am at work.

Is it your transmission? My Getrag makes the same noise. Been meaning to have it replaced.

Does it change with throttle load? Say you're at 1700 RPM cruising with about 15% throttle applied, once you go around 80-100% does the noise go away?
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Old 09-06-2018, 10:54 AM   #3
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Could be the waterpump nearing its end. Too vague to know though.

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Old 09-06-2018, 05:15 PM   #4
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Sure it's not a rattling heat shield/exhaust shield/other loose bit of metal? Or loose exhaust bolts? That's what it sounds like to me.
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Old 09-07-2018, 08:52 AM   #5
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Louder inside the cabin normally points to driveline or exhaust. You said it does it with the clutch pressed in/out, so check for exhaust leaks.
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Old 09-09-2018, 07:12 AM   #6
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I don't think it's your distributor...


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