Bad vibration??

[sparkysi90]

Hi

I have just fitted eibach ARB'S Bilstein b8s and eibach springs to my s3 new drop links too. To fit the front ARB i had to take the subframe down and release the dog bone mount etc. (dog bone is red diesel one fitted a month or so back)
Since I have done this the car vibrates alot on idle and also the engine sounds.... noisier??And when revving there's alot more vibration. There's also an awfull fast metal rattling (not a loose rattle more of a mechanical rattle) coming from what sounds like possibly the drive shaft area? Once you take your foot off the throttle not when accelerating.

Any one any ideas what this could be? There's nothing loose, I torqued the dog bone mount and can't really see anything with a visual inspection!

Thanks

Simon

 

[scotty_24]

Do you have a 3" downpipe ?
Moving the subframe the downpipe could now be hitting the rack or body causing vibrations at idle

 

[Jutchops]

Sorry couldn't quite make it out from what you put, you've had the end dogbone mount in for a month without issue? When it went in originally was it torqued in the same way it is now? The rest of work could be a red herring..

 

[ayfreetee]

Poly bushed dog bone mounts can cause vibration at certain revs, worse when the air con is switched on.

 

[sparkysi90]

No no issues what so ever with the dog bone mount before and it's torqued same as before. I don't think that it's the dog bone mount to be honest, its the first thing I thought and have triple checked it?

Exhaust is standard.

I

 

[Jutchops]

I guess my concern would be given all the parts you changed and effectively stiffened up is that you've removed the ability of the original components which were probably a lot soggier, especially if original, to absorb the vibrations and now it's getting transmitted through the body and resonating as you describe. Why did you go red dog mount and not just a normal upgrade?

 

[sparkysi90]

Yeah this was my concern also.
Although the rattling type noise is defiantly not good.
Went for red as alot of people recommend it and say it gives better ride comfort over the yellow one

 

[ayfreetee]

On over run, it could be the cat is starting to fall apart, causing the rattle you describe.

 

[Stuartgib]

Had similar to this before and turned out donought had perished at rear propshaft joint you may want to check this out

 

[sparkysi90]

Thanks for replies I found the problem in the end. Ended up being the two solid black pipes that run behind the gear box near front ARB squashed between the ARB and gear box :-s. What do these pipes feed?

Thanks