Annoying crunch noise over speed bumps

[eniacs]

I've got a 2014 1.6tdi fabia, its a cracking car, 150k miles on it, picked it up a year ago for £2k. Its been very reliable and returned 40-70mpg over the time.

 

However i've a problem with speed bumps, they make a crunch sort of noise when going over them. Following this forum i've changed the anti roll bar bushes for new and then the ARB drop links. However its still remaining!

 

Any further ideas? Lower arms? Shocks? Springs? I've inspected everything visually and nothing is obviously wrong.

 

Thanks

[thomasaspin]

Could be a broken spring ? Or a failing suspension gas strut 

[eniacs]

The spring isnt broken, that was one of my first thoughts too!

 

Is it a shock problem? It doesnt make noise any other time, how can i test it?

 

 

[skomaz]

It'll be the suspension arm bushes...   and the rubber in them.  A shot of spray grease should sort it for a while but it'll come back eventually.

[Ootohere]

Often you can not see the broken spring right up at the top.  Drivers side most often. But then if only it was changed last time it can be the passenger side this time. 

[nta16]

Please note - I am not a mechanic or expert in anything.

 

Springs can break near the top where it's difficult to see. * ETA: I was still typing and toot has put better info on this.

 

I like the idea of spray bushes but not so much with grease as this tends to hold grit/debris, instead I'd spray with GT85 (PTFE included) as a spray soaking might wash some stuff out but leaves a non-sticky layer of lubrication.  If you can be bothered to spray one thing at a time you could find the actual source be it a bush or not.

 

https://gt85.co.uk/gt85-original/

 

GT85 is also handy for loads of other jobs that require a lubricant, penetrating/releasing agent, cleaner, and it smells nice.  It's also a water displacer so you can give up on the inferior WD-40 Multi-Use spray (though sadly both are now from the same  company.  I used to use GT85 on my pushbikes in the 1980s and returned to it in more recent years for car and home.

 

I used it to locate the noise on a water pump and alternator drive shaft on a couple of different vehicles and the noises didn't return so I guess the GT85 flushed away the grit and or lubricated but really I don't care as it done the job without getting my hands dirty and with very little effort which is the only way I like car repairs/maintenance/servicing.

 

Edited 23 December, 2022 by nta16
ETA:

[nta16]

14 minutes ago, toot said:

But then if only it was changed last time it can be the passenger side this time. 

Was talking about this only this afternoon with my neighbour when I ordered what I thought was a set of springs on special offer to discover I'd got it wrong it was a single so I gave it back to the driver and had to cancel with the site, my neighbour asked who fitted only one side and I explained Dealerships and customers who insist on it.

 

Last set of front road springs I fitted were proper rolled steel, you can still get them (for old cars at least) and they were not expensive could also be made to specification if required, I almost fitted modern (AreO bar) springs until a mate told me how often they break on modern cars.

  

Edited 23 December, 2022 by nta16

[eniacs]

Ok i will check the springs first i suppose as many have suggested, camera phone to take a pic?

[nta16]

Please note - I am not a mechanic or expert in anything.

 

8 minutes ago, eniacs said:

camera phone to take a pic?

Might be difficult on light and focus and angle.

 

If you can wait until after all this Xmas and New Year madness (no I'm not a fan 🤐 ) you could order one of these dirty cheap endoscope (attachment(?) things to a "smart" phone/device?) which you could twist in and around the area better.  Seen the cheap stand alone units on American videos but most car related stuff is a lot cheaper and easier to get in America. much of it made in China of course. 🤣

 

Edited 23 December, 2022 by nta16

[eniacs]

Passenger side:

 

Drivers side:

[UrbanPanzer]

5 hours ago, skomaz said:

It'll be the suspension arm bushes...   and the rubber in them.  A shot of spray grease should sort it for a while but it'll come back eventually.

 

if not broken spring, then agree with the above.

Edited 23 December, 2022 by UrbanPanzer

[Murdockman]

You cannot always see the crack some times you need to removethe spring to find it, the noise can also come from a broken suspension bush as the Fabia bushes are rubbish,I replaced both mine on our mk2 with seat curra bushes that are solid rubber and lasted 8 years beforecar waswritten off by an uninsured driver, the Seat bushes are around £50 for a pair but well worth fitting them

[Bertie90]

I have a Fabia and a roomster and both have the same noise over speed bumps when it's cold. Its the ARB bushes, even when new they still squeek. Never seen anything like this in any other cars apart from VAG. 

 

Spray some silicone lube over them and you'll see it will go away for a day or two. do it in stages to trace the sound.

[eniacs]

Thanks all. I will go and apply some grease to the other joints. I did grease the arb bush when installing. Went out today in it and i think its a lot better. Will try the lower arm bushes and see if that makes it even better, suspect they are the ones from factory! After 150k miles they will be a little worse for wear

[Asketi]

I have exactly the same car, model year etc.

 

I also had this issue when my car was a year old.  The noise was a crunch and seemed to come from the passenger side of the vehicle.  It only ever happened when going over larger speed bumps.

 

Skoda changed the control arms (didn’t fix the issue) but the problem eventually was identified a problem with the steering rack (didn’t make sense to me).  But it fixed it!

 

 

[eniacs]

Oof hope its not the steering rack! Only thing left now is control rods and lower arms. Its less of a loud noise now though.