Loud tinny rattle

[JC46]

Iv been lurking around here for a few months, but I've decided to finally post after my 2006 gti started making a loud tinny rattling noise, I can't see any bits of heat sheild ect that might be causing it.. It seems to happen sporadically but goes away when I rev it. It's a dsg so I thought it could be the dmf problem but the gearbox seems fine, totally smooth. I had it in at a vw dealer for the timing belt so I asked them to have a look for wear in the cam chain but they said it looked fine and they never herd a noise, But it's still doing it. Could anyone give me an idea as to what it might be? Cheers!

[scopes]

See if you can post a video of the noise up.  The TFSI engines are very much a tappier engine... Some say it sounds like a diesel engine ! 

[dansmith180]

Probably the good old fuel line rattle, under the car behind the plastic on the drivers side (i think but could be passanger side) the fuel lines rattle. Just search for MK5 golf fuel line rattle on here and you'll find a few threads that will tell you how to sort it in plenty of detail.

[mac456]

Does it happen after you rev it? And at idle? And when you press the accelerator it goes away?

[dansmith180]

I found its always at idle mostly when the cars warm but sometimes when its cold and as soon as you rev it goes away.

[mac456]

It sounds like the wastegate on your turbo is faulty, mines the same and so is a few others with the tfsi engine.

From what I found its slightly common on this engine. Audis, VW's etc....

Basically when you let off the boost, the wastegate rattles and when you rev it the wastegate close's and seals (stops rattling)

I had mine checked by a turbo specialist and even though it rattles off boost it works perfectly on boost (hitting correct psi) so he recommended just leaving it.

[JC46]

Thanks for the replies everyone, it happens randomly.. It can just be idling fine them makes the sound for a short time then of again. Here's a short clip of the noise, it goes away at the end.

[JC46]

Anyone know what it is?