That's more than likely your tyres losing grip and the front of the car bouncing slightly.... commonly refered to as axle tramp.
Well, suspension upgrades can help. Wheel balancing also.
Though I have found that tyres can certainly be a cause.
Thats funny my last car was an Astra Turbo and I had the exact same thing, a raspy, mettalic rattle at certain Revs..
First was told it was the Cat converter, then the exhaust, then the turbo... Basically they had NFI..... didn't affect the car in any way...
....until the turbo blew up..
Nah just kidding, that was one of the most reliable cars I've ever owned.
2017 MY18 Golf R 7.5 Wolfsburg wagon (boring white) delivered 21 Sep 2017, 2008 Octavia vRS wagon 2.0 TFSI 6M (bright yellow), 2006 T5 Transporter van 2.5 TDI 6M (gone but not forgotten).
I took a GTI for a second test drive over the weekend, and specifically tried to replicate the rattle (the demonstrator had 70kms on the clock).
You can definitely notice it if the conditions are right - ie windows down, stereo off, a certain amount of revs, a certain amount of throttle. Even then, I only noticed a faint rattle about a quarter of the time.
However, I don't think many people would notice it if they weren't told it could rattle to begin with.
So does it get to the point where you want to sell the car and get rid of it because it is annoying?
So far its been as annoying as having a fly buzzing around your ear every now and then...... still love the car! just got the ECU flash a couple of days ago and planning to do a couple more things to it....but still hoping someone out there will find a fix soon.
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