Cupra Bush Install: What's with the Boom?

[pyromorph]

Hi,

Just installed the Cupra bushes to my vRS, the old bushes were on their last legs... However as soon as I took it for it's first ride I notice the seriously loud engine / exhaust like booming noise below 1500rpm. As soon as it gets to 1500rpm the noise goes. It appears it makes it when there is a little throttle, such as when commuting in slow traffic etc...

Anyone else got this problem?

Thanks,

Phil.

[warwick hunt]

can only be sumthin vibrating....make sure jobs been done correctly.

[BRUN]

its common with the cupra bushes

[br1anuk]

its common with the cupra bushes

I've fitted them to my Elegance tdi and yes there's an annoying boom, changing down all the time is annoying.

Brian

[Big Gray]

Perfectly normal, the solid cupra bushes pass more vibration into the cabin.

Graham

[faboka vrs]

Yeah that's normal.I think it's down to using too high a gear. Just amplified more with the cupra bushes. Easy solved by using a lower gear.

[Guest]

how bad is it out of ten was looking to get them done, when i get my coilovers

[pyromorph]

how bad is it out of ten was looking to get them done, when i get my coilovers

Well it depends on your driving style I suppose. I cruise a lot and often find myself in the < 1500 rpm band just cruising along... so for me it's very unpleasant. I've had to start to retrain myself to keep at 1.5k and above. This means 2nd gear instead of 3rd etc.. Don't get me wrong, the bushes are a seriously good upgrade if your old bushes were shafted, like mine. In terms of how bad... I'd never buy a Ibiza Cupra if it sounds like this.. so I suspect that they've engineered it out somewhere else... I've got the new dogbone mount as well.

I do however recommend that you look into the X-Bushes

... When I bought the bushes from the SEAT dealer he mentioned that they weren't allowed to install the solid ones any more as they had been superseded and the solid bushes (the ones I used) are for retail only. The X-Buses are void bushes like the originals.. just better I suspect. I recon the Void bushes will give less noise in the cabin.

How bad? 6/10

Phil

Edited 2 May, 2010 by pyromorph

[pyromorph]

How bad? 6/10

After driving the car for a couple of weeks I'd like to revise my previous statement on how bad it is. First of all, changing my driving style is an on-going process... harder that I expected after cruising at low revs for so long.. however, it's not really effected my MPG in any noticeable way ... which was my main concern. Also, the boom isn't too bad, I suspect that over time it will slowly get better as the bushes wear in. With the revs always being at 1.5k or above the throttle response is much better..

How bad? 3/10

[mod_boy]

i have some brand new cupra bushes sealed if anyone is interested?

[Rob.]

I think this is what I've noticed in the past.

Seems to have more of an effect in cold weather.. I guess because the rubber is stiffer due to the lower temperature.

Just to be sure though, are you noticing a little more engine vibration through the cabin in general.. no where specific.. just more of a buzz? Not much though, just a tad that wasn't there before?

I've been suspecting worn engine mounts.. but maybe It's just been these bushes all along?

Taa

Rob.

[Padda]

I had this upgrade done a month ago because my stock bushes were wearing. First of all steering seemed more responsive but noticed the noise increase as I too cruise....

Then I noticed a rattling when staionery, odd - turns out my DMF is failing (but thats another post)

[pyromorph]

Just to be sure though, are you noticing a little more engine vibration through the cabin in general.. no where specific.. just more of a buzz? Not much though, just a tad that wasn't there before?

It sounds almost like the exhaust is blowing.. strangely enough.

[giandougl]

Its seems CUPRA bushes are more solid than standard dainty SKODA bushes.

Sound will be transmitted everywhere possible, it seems the price you pay for stiffening up things..

Bushes are fairly easily replaced, with SKODA bushes, and if DIY, a cheap job too.

[mugs]

I had my console bushes swapped for the Cupra ones yesterday and my car is MUCH noiser than before, I'm getting all sorts of vibrations and resonance. I put it down to the 1.4 being a bit choppier than the 4-cylinder engines but it was a touch surprising just how loud it all was. It gets better at higher revs, so I spent most of the drive home in 4th instead of crusing along at 2k rpm in 5th like usual. I've got my fingers crossed that once the bushes bed in the boominess will settle down, but considering how quickly the standard skoda bushes wear and the cost of getting it done at a garage (you'll still have to pay for alignment even if you diy) then I'm happy to put up with the increase in noise purely for longevity. It's also transformed my gearchange, it was sloppy and notchy before and now it's sweet as a nut - dogbone mount is next on the shopping list, it's amazing the difference new bushes can make.

[Hauptmann]

Having now fitted a number of these Cupra bushes I'm baffled by some of the posts above. Nobody has noticed any booming or significant extra noise on the ones that I've done. There is a little more road rumble - that's all.

These bushes sit between the chassis and wishbone, so I don't see how they can possibly transfer any additional engine or exhaust noise to the cabin. I would also say that its impossible for them to alter the feel of the gearchange. I suspect that in some cases someone has undone bolts and allowed the subframe to move and change its alignment slightly - I think that's the issue... That would change the loading on the engine and gearbox mounts and this is why you are getting booming and vibration - its nothing to do with the wishbone bushes, its the way the job's been tackled.

Edited 14 May, 2010 by Hauptmann

[pyromorph]

These bushes sit between the chassis and wishbone, so I don't see how they can possibly transfer any additional engine or exhaust noise to the cabin. I would also say that its impossible for them to alter the feel of the gearchange.

I agree on the gear change as that would be related to the gearbox mount / dogbone mount etc.. however the increase in cabin noise at low revs is not so much of a stretch.. The bush connects the console (chassis) to the wishbone which in turn is connected to the wheel via the ball joint. The drive shaft could easily transfer noise to the wheel, which is isolated at certain frequencies by the tyre rubber. I suspect the solid bush allows a resonance to take place at lower frequencies which might explain why they've been superseded by the X bushes. The original Skoda bushes must have had a least 70% less rubber in them and would not be prone to the same issue. As to why some cars have the noise and other don't.. It's likely that the culprit wasn't noticeable before the cupra bush install, so your guess is as good as mine. It might be that other bushes, maybe the ones at the front of the wishbone might be on their way out and would normally carry the vibrations out the other direction.... who knows.

[rum4mo]

Having now fitted a number of these Cupra bushes I'm baffled by some of the posts above. Nobody has noticed any booming or significant extra noise on the ones that I've done. There is a little more road rumble - that's all.

These bushes sit between the chassis and wishbone, so I don't see how they can possibly transfer any additional engine or exhaust noise to the cabin. I would also say that its impossible for them to alter the feel of the gearchange. I suspect that in some cases someone has undone bolts and allowed the subframe to move and change its alignment slightly - I think that's the issue... That would change the loading on the engine and gearbox mounts and this is why you are getting booming and vibration - its nothing to do with the wishbone bushes, its the way the job's been tackled.

I fully agree with you, yes there will be a little more road noise as the solid bush is stiffer, but in my case - Polo 1.4 16V SE - it is not really noticable at all. Booming etc as you say might be getting caused by the front section of the exhaust starting to touch the crossmember for the reason that you have given. I would hope the only comments that people would be making was that the feel of the steering has sharpened up considerably.

[pyromorph]

I fully agree with you, yes there will be a little more road noise as the solid bush is stiffer, but in my case - Polo 1.4 16V SE - it is not really noticable at all. Booming etc as you say might be getting caused by the front section of the exhaust starting to touch the crossmember for the reason that you have given. I would hope the only comments that people would be making was that the feel of the steering has sharpened up considerably.

But wouldn't that cause knocking due to the engine vibrations?

After driving the car for several 1000 miles since I installed the bushes, It really does seem to be exhaust related and it does just "vanish" when you hit 1500rpm, and it's independent of gear.

When I next get chance I'll have another look, but I'm pretty certain that the exhaust side is suspended ok... I looked back through my parts history for the car, I bought it several years ago at 24k and it's now on 86k, lives outside and it's still on it's original exhaust. Perhaps during the install something got knocked and now it's on it's way out ( small hole etc.. ) ... As I say.. I'll take another look.

Thanks,

Phil.

[Tech1e]

Having now fitted a number of these Cupra bushes I'm baffled by some of the posts above. Nobody has noticed any booming or significant extra noise on the ones that I've done. There is a little more road rumble - that's all.

These bushes sit between the chassis and wishbone, so I don't see how they can possibly transfer any additional engine or exhaust noise to the cabin. I would also say that its impossible for them to alter the feel of the gearchange. I suspect that in some cases someone has undone bolts and allowed the subframe to move and change its alignment slightly - I think that's the issue... That would change the loading on the engine and gearbox mounts and this is why you are getting booming and vibration - its nothing to do with the wishbone bushes, its the way the job's been tackled.

I agree, don't see how it's connected myself, never had the problem either.

[mogwye]

I too also reported exactly the same 'booming' findings 9 months ago, I fitted the cupra console bushes (solid) and the powerflex front bushes to my wife's 1.4 TDI and below 1500 rpm you get the feeling that the engine is vibrating, so changed the dogbone to no effect, the noise is still there and very annoying at having to drive in the manner of keeping above 1500. I originally suspected the powerflex bushes as the cause but reading through the above posts seems to point to the solid cupra bushes alone.

On my 1.4 TDI the console bushes (latest Skoda ones) were replaced under warranty and are great with no noise and much nicer to drive and can even drop to 1000 rpm without vibration..

The extra vibration and noise only appear to affect the 1.4 TDI engines fitted with the SOLID cupra bushes - so be warned.

DB.

[rum4mo]

I too also reported exactly the same 'booming' findings 9 months ago, I fitted the cupra console bushes (solid) and the powerflex front bushes to my wife's 1.4 TDI and below 1500 rpm you get the feeling that the engine is vibrating, so changed the dogbone to no effect, the noise is still there and very annoying at having to drive in the manner of keeping above 1500. I originally suspected the powerflex bushes as the cause but reading through the above posts seems to point to the solid cupra bushes alone.

On my 1.4 TDI the console bushes (latest Skoda ones) were replaced under warranty and are great with no noise and much nicer to drive and can even drop to 1000 rpm without vibration..

The extra vibration and noise only appear to affect the 1.4 TDI engines fitted with the SOLID cupra bushes - so be warned.

DB.

I still think that you should get the car up onto ramps and check over the area where the front section of exhaust passes the crossmember, I got a new flexi pipe welded into my wife's Polo 1.4 16V SE and the noise was terrible - both booming and roughness at certain revs, the guy that did this work was a specialist exhaust builder so it took quite a lot of convincing him that the car was very noisy only after he changed the flexi, which by the way was the next size or two up (and so the booming!), the roughness was just slightly inaccurate aligning prior to welding. The next time he did that job with a flexi that I bought, the car was a quiet as it had been when new. If the exhaust is just "kissing" the crossmember it will get very rough at certain revs. You might get away with slackening off all the joints and moving it a bit so that it looks like it is well clear of the crossmember - and you might now need new "rubber" hangers to keep it in the right place.

[mogwye]

Very interesting, however the garage (non Skoda) that did the work replaced the bushes with the consoles in situ (at my request) to avoid having to re-track, therefore I very much doubt that the exhaust is hitting the subframe.

But you never know, I will check out your theory and hopefully it may resolve the matter because it's so bad that I was considering having the bushes replaced with the latest Skoda ones.

Thanks for your input.

DB.

[mogwye]

On second thoughts.

Prior to having my console bushes fitted, I had the cam belt changed at a Skoda dealer, after fitting I had several noisy bulkhead related problems, the main one being that the bracket holding the water heater tubes to the bulkhead had been fractured and other pipes were floating around having been dislocated from their holding clips, causing horrendous rattles and vibrations.

The so called 'mechanic' had obviously jacked up the engine to gain better access to change the belt and had forced the engine to the point where the above bracket was snapped and the other pipes were wrenched out of their clips. The car had to go back on 3 occassions to rectify the bulkhead noises.

Once sorted there were no other noises even when floating along at 1000 rpm in 4th gear.

However I am now wondering whether the exhaust or it's heat shield could have also been bent in the botched cam belt change and the vibation noises have only come to light after the stronger console bushes were fitted, hence the previously mentioned replacement of the dogbone mounting as a possibility to iron out the vibration.

I will have to investigate the location of the exhaust and heat shield further.

DB.

[pyromorph]

If the exhaust is just "kissing" the crossmember it will get very rough at certain revs. You might get away with slackening off all the joints and moving it a bit so that it looks like it is well clear of the crossmember - and you might now need new "rubber" hangers to keep it in the right place.

That's given me something to go on. As it's the original exhaust, the hangers are proper worn. I'll just have to jack it up and have a look.

Thanks for the advice.

Phil.