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G60DEE

Rattle at 2500rpm

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When i'm driving around, something in my C's engine rattles but it only starts rattling around 2500 rpm. Its definatley not the charger but its coming from the back of the engine. in 12 months the noise hasn't got ant louder or quieter, but its still there. Any ideas?

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I have a similar problem to you. Mine starts at about 2800 and then fades just of 3400.

 

Mine also has got no louder or quieter over time, and the temp of the engine doesn't effect the noise either.

 

Any ideas why anyone?

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This could be the Heatshield around the exhaust downpipe.

Mine has a similar rattle which was annoying for a while. I discovered what was causing it whilst replacing the lambda sensor in the exhaust.

I could see there was a split in the heatsheild & it was vibrating against the downpipe.

The only way to remove the heatsheild is to take off the downpipe.

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dazzyvr6, I would tend to agree with you there.I had the same problem with my G60, just rip it off and throw it away.Job done. :lol:

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The heat shield above my back box is loose and rattling, would it be ok to throw that away, I dont imagine the back box gets that hot that its really required?

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I had a similar problem on a Scirocco.

 

It was a tiny little rattle. It usally stoped when I toped up the water level. I thought that it may have been something to do with the thermastat opening and closeing.

 

Not sure about that but give it a try!

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If your going to take the heatshield off replace it with some exhaust insulation wrap you can buy it from demon tweeks and it will keep the heat away from any wiring looms or pipes around that area, without it you might find you will get unexpected problems occur!!

 

Thats my two pennies worth anyway!!!

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Joe M, next time you've had your C out, touch the tip of the exhaust mine gets farly warm!!

 

Oops, I meant compared to the rest of the exaust. I know it gets hot but I think its only really the floor of the car above the backbox, nothing that will really matter with the heat I would think.

Ill have a better look under the car when the weather improves and try securing the one ive got.

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I had a similar rattle on the 16V and was convinced it was from under the car/engine bay. Spent absolutely ages trying to find which bit of heat shield or whatever was loose. After months of going mad with it I finally tracked it down. The roof lining has a plastic trim strip running across the top of the windscreen and is held on with metal spring clips. A couple of these had broken allowing the strip to resonate in a particular rev band. Wouldn't have believed it if I hadn't seen it for myself. Get up to rattle speed and then run your finger along the strip - if it shuts up then thats it. Its a bit of a swine to get the strip off without damaging either it or the roof lining so go careful - refitting is also a bit tricky to get it lined up. New clips are pennies. The silence was golden.

If it ain't that then who knows. Or try turning the radio up instead - that works

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2cc our electricain has promised the looms in at the end of this week if you are still intrested.......

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Darren,

Absolutely mate, I want two of them please. Let me know how much overall with P&P etc & who you want the cheque making out to an I'll get it in the post

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I'll give the exhaust a good goin over when the weather is better

Cheers for tips guys, although i'm 100% sure its not the windscreen, thanks 2CC!!

I can hear the rattle resonate through tunnels and stuff.....

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Just to add to these comments - my Golf GTI 8v had a really annoying rattle between 2500rpm and 3k - it was indeed the heatshield on the downpipe - me and a mate got the car on ramps and put a couple of long bolts in it (it should have 3 as standard, but they tend to fall off - 2 of mine had!) and it pretty much cured the problem!

 

Hope this helps

 

Dave

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hi, i posted something similar on the servicing forum, ive got the same problem on my 16v,

is the downpipe heatshield supposed to be in 2 parts? or is mine split down the middle?

is there anyway of removing/replacing the heatshields without taking the downpipe off?

also a little unsure about how they actually attach to the pipe

 

thanks

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The downpipe heatshield is spot welded down one side. It's held in place by a bolt which goes inbetween the 2 pipes.

I got mine off by cutting sections off with a pair of tin snips & then bending & twisting the top part off the bolt with a long screwdriver.

It took about an hour to do, but the it's soooooo much better without that rattle.

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Can anyone say whether they also got this rattle when pulling away as well? I have what sounds like exactly the same problem but after extensive investigation (by me and an exhaust specialist) the determination was that it was the tailpipe on the custom exhaust rattling against the rear valance. The rattle on mine also kicks in at 2500-3000 RPM but like I said, I also get the same annoying rattle when pulling away.

 

I would have to say that you can FEEL this rattle through the seat of your pants so I'm more inclined to think it really is the tailpipe hitting the valance. However, if what I am describing rings any bells to anyone then please let me know. It would be nice if this was something as simple as a loose heat shield.

 

Oh - FYI. I had a Mk-II Golf many years ago and the heat-shield dropped off the downpipe from the outlet manifold. I just threw it away and thought nothing of it. Two MoTs later I was informed that the bulkhead had been damaged by the excess heat and would need to be cut out and replaced! Exit one otherwise perfectly good Golf. Moral of the story: heat shields are there for a reason so throw them away at your peril.

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grugh wrote

Can anyone say whether they also got this rattle when pulling away as well? I have what sounds like exactly the same problem but after extensive investigation (by me and an exhaust specialist) the determination was that it was the tailpipe on the custom exhaust rattling against the rear valance. The rattle on mine also kicks in at 2500-3000 RPM but like I said, I also get the same annoying rattle when pulling away.

The Cat stone guard rear fixings on my VR are prone to letting go and then rattle on pulling away - doesn't happen when motoring. Have to say kind of a light tinny noise rather than the 'seat of pants drumming' you describe. I know you had a good look but did you notice that bit?

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Cat? Ummm...don't have one of those! (:D) It seems to have vanished when the new exhaust went on. I'll take a look at my heat shields tomorrow but I'm betting on the rear valance. When the car is up on ramps if the exhaust is swung it smacks nicely into the valance and while it has to move quite a bit to do that I'm putting my money on that being the problem.

 

Someone did suggest spacing out the last hanger but I'm already a touch worried about clearance over the rear axle so that may not be the best solution.

 

I'm actually not at all impressed with the fit of this exhaust but as I didn't pay for it (or to have it fitted) I guess I can't complain too much. Plus, I do rather like the way it looks and sounds!

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How much clearance is there between the curved pipe at the backbox and the bottom of the car. When the fitting of mine was slightly off it was fine when cold but when the exaust had heated up it would start touching the bottom of the car and made noises at certain revs.

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Sounds like a very similar problem. The real issue I have is that where the tailpipe comes out of the backbox it has a very pronounced upward angle between the box and the outlet. As a result the exhaust has had to be slung pretty low (probably as low as they could get it) but the tailpipe is still very high. I guess I could just have the backbox replaced with something that has a less aggressive upward angle on the last section of pipe but it is a brand new exhaust, fitted less than six months ago, and I can't really afford to shell out a couple of hundred quid when I have more important things on the 'to do' list.

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After another visit to the exhaust people my rattle is now fixed. Apparently the back box had moved (or not been fitted properly) so it was re-mounted and now all is silent - apart from that nice burble which is what I want to hear!

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mine rattles too in the same rev range 2300-3000rpm gonna have a go at the heat sheild over the weekend

 

ps: anyone want to buy a 1972 beetle - tax exempt - nice little project for the summer -

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