Peculiar rattle won't go away

[vborovic]

This is a tough one ... since obtaining a car several months back, the car tends to produce a sound (not always though), which is very much like a loose plastic that rattles while going over small horizontal bumps ... but then again, it can start producing the sound while traveling on a straight road and it will continue to rattle unless I slow down or accelerate (like it is caused with the wind, pushing something loose, just enough to vibrate around ... now, the sound intensity is constant when this happens ...

 

I've had the front silent blocks replaced on both wheels, didn't' improve one bit

I've replaced the rear shocks bumps stops (the plastic caps were down near the wheel, they did rattle, but this is something different)

I've replaced the rear struts (Sachs selected), nothing changed

I've had the front and rear stabilizer links replaced as well, no improvement

I've emptied the boot, including the emergency wheel  from its well, didn't help

Everything that cold be removed from the cabin, doors, compartments was also checked, nothing obvious

I've taken down the front wheel arches plastic covers and the central engine bottom cover (which needed to be replaced anyways) ... the rattle is still there ...

 

I'll take off the central bottom plastic covers, that protect the chassis (if nothing else, I'll remove the debris, dirt and gravel that's probably stuck behind it) ... I can then eliminate the rear wheel arches plastic covers (though I don't think they're the culprit) ... from the driver's seat (steering wheel on the proper, left side of the car ), the source of the sound appears to be the rear right wheel (although, it sometimes seems to me like the source comes from the front, but definitely the left side of the car) ... I've passed the MOT two months ago, the car had its suspension tested, the rattle couldn't be reproduced then ...

 

Any ideas what to try next? I'll tear the whole car apart if I have to, the noise has to go away (the car's ride  quality isn't suffering in any way, but it is silly to drive around a car like this and have something stupid rattling around) ... of the other things that might be worth looking into, the CV joints, the wheel bearings ... ?

[CombatWombat]

I once read on a forum (can't remember the car manufacturer) about how a weird rattle was traced to a child's marble that had got into one of the heating vents for the rear of the car.  Or what if something similar has got underneath the back seat base and is moving around in the general area above the fuel tank?  Just a thought....

Edited 6 April, 2018 by CombatWombat

[Superb170]

Sounds like what I had on my old Superb which I posted a few years back.  It was stone chippings lodged in the under tray cover as you mentioned.  Worth looking at it as it might just solve your problem.

[vborovic]

@CombatWombat - I can't be 100% sure, but I believe I've cleared everything inside the cabin that was accessible or half-accessible (I didn't remove the door panels to check for loose cables, but I don't think that's the source of the rattle)

 

@Superb170 - That's why it is next on my list, hopefully tomorrow or the day after, but I find it hard to believe such a sound could be made and replayed over and over, to me it sounds like it is something bigger, at least bigger than a stone, like a half-broken plastic housing that rattles against another piece of plastic

[mac11irl]

Swmbo's citigo had a rattle that turned out to be a dash mounting clip that split off and the plastic tab had fallen down the bottom of the dash panel and was buzzing on the inside. 

Took theguys in the workshop a full day to strip it down, found a 1inch piece of plastic took it out reassembled and the rattle went.

 

But somebody twisted the vent setting dial on reassembly so the fan setting was all over the place.. poor barstewards had to spend another half day stripping it downagain to reset it  (all under warranty and a nice new fabia 3 courtesy car for a couple of days)

 

It could easy be something stuck in a vent pipe junction, falls onto a joiner and rattles, dislodges and falls to a softer piece and stops... until it rolls back again..

[Wile7]

 

[superbdreams]

front facing left vent, chrome surround.

extensive threads on this.

[vborovic]

After being 5 hours down under the car (down under ... get it? ... I know, it's not that funny actually) I can tell you what isn't making the rattling noise ...

 

Engine under tray (old & new) - it had only one main bolt attached to the plastic, it was dangling around, and it was cracked on both sides, potentially falling off with the next encounter with whatever you can hit under the car. You can also see traces of oil on it, I think it is the engine valve rubber seal, will get to that soon  ... the new plastic tray, after being securely tightened, doesn't make any noise, can't hit the gearbox while moving around, and it holds the front wheel arches plastic covers more securely in place.

 

 

 

Under body plastic covers (both sides) - removed the debris, dirt and gravel that was in them, not that much actually (if no one removed them for 10 years)

 

 

 

Don't ask - some kind of hard pipes that are going from the rear left wheel arch towards the front (under the rear left passenger, before & after) ... the left one on the picture could produce sound to the chassis behind it (but probably not during normal driving conditions), I've used a plastic strap to just slightly pull it closer to the right one, now there is no way for it to make any sound

 

 

 

That's only part 1 of 2 ..

 

[vborovic]

The driver's side behind wheel arch plastic cover (that holds in place the left side plastic body cover) - it was missing, so I've ordered it (cost 1.5 GBP - yes, I've written int correctly) and attached it to the chassis.Holds the plastic cover in place nicely.

 

 

 

Metal "nuts" that hold the exhaust thermal insulation to the chassis - this was a WTF moment of revelation - who in their right mind designs these things - the rust ate two of them away (symmetrically on each side), and the front part of the middle insulation metal sheet was freely thumping around ... I hope this was the rattle-maker while driving in certain speeds, which could start vibrating on a normal, straight road, probably due to wind turbulence under the car. I've applied some Nigrin Anti-rust spray (that clears it away and provides metal protection), put a M5 nut with a washer below it, and tightened it in place (times two), and now the thermal insulation can't make any noise even if it wanted.

 

 

 

 

 

Fuel line from the reservoir to the front (passenger side - right side of the car) - unintentionally, I've figured out that the fuel line and the other pipe that goes parallel with it can rattle within the chassis, so I've put some rubber as a strip inside, to envelop the pipes and reduce the chance of them rattling.

 

(photos in the following post due to size limitation)

 

Apart from that, I also did some modifications to the exhaust (mine is custom), there were U shaped bolts holding a connection pipe together, rotated them around to avoid them hitting the reservoir metal plate protection (that would have to be very sever vibrations of the exhaust pipe for that to happen.

 

Used the chance to inspect the chassis from below, it isn't as rusty as you might expect of a 10 year old car, though the suspension parts, bushes and some other components show signs of rusting, front and back (the back is in worse shape). I've also noticed that the Haldex behind is greasy, probably the seal ring is leaking somewhere, but as I've intended to do its oil replacement anyways soon, this will be done as well (I believe I'll have to dismantle the rear wheel driveshaft that goes to the Haldex - supposedly a PITA ...

Edited 7 April, 2018 by vborovic

[vborovic]

Fuel line situation

 

 

 

 

[vborovic]

Next on my to-do list is to remove the rear wheel arches plastic covers, they seem to be able to produce rattling sound fairly easy, just by lightly touching them near the rear suspension strut, and in turn they make a sound by making contact with the chassis behind them ... this can be a simple fix, just put some rubber behind it (with a double-sided tape), and no sound from them ... what I will find when I take that off, I don't know, but I still think that the rear left wheel location is the most likely source. I've checked the chrome surround of the front facing left vent (actually, I checked all the vents), they're making no sound at all (although they could use a bit of cleaning, the plastic flaps need to be de-greased).

[TasMan]

The only odd rattle outwith the cabin I have had was a flexible plastic breather pipe on the right hand side of the engine bay near the air box (when standing in front of the car).  Pipe was snaking around loose and rattling off other parts around about.  Was worse at certain revs and the dealer spotted it while I was revving the engine, it was quite obviously waggling around.  A cable tie isolated that issue and its been quiet since.  Don't talk to be about cabin squeaks and creaks....! :-)

Edited 9 April, 2018 by TasMan

[Lucchese]

Are you hearing from inside the car? around the drivers foot well / centre consul?

[vborovic]

From inside the car, and it mostly sounds like it is coming from the rear left wheel position

[Lucchese]

I had what sounded like a “rattle” from under the steering column, it turned out to be be the plastic trim rubbing on the metal plate. It took me a long time to find as it sounded it was coming from the rear!!

 

The other areas I found rattles were:

• door card rivets (quite random, door card off and replaced them)
• door latch (solved this with black tape on the catch)
• boot door stops not set correctly (adjusted and ok)
• all the air vents as already mentioned (I use a food grade grease around them all)
• passenger sun visor (grease again)

i have had had some others but not too bad.

 

not sure if this helps

[vborovic]

A few fresh ideas, thanks. From time to time I also find some potential noise sources and tape them or use plastic straps to hold cables or similar flexible components in place. If (and when) I find the source of the rattle, I'll let everyone know what it was.

[Lucchese]

I hope you find the source, I find rattles and squeaks very annoying.

 

keep us updated

[vborovic]

Did a 375 mile trip yesterday, mostly highway, and the rattle is still stuck with the car ... now the main suspect is the exhaust pipe(s), that somewhere a part of it came loose and tumbles around as the car vibrates on bumps ... while I was under the car doing cleaning of the plastic covers under the floor, I've tried the movement of the exhausts system by hand, nothing obvious that would suggest that something is too loose, maybe I'll go to the exhaust specialist to take a closer look, it will be very funny if it is something simple (as such issues usually are)

[Lucchese]

On 22/04/2018 at 21:23, vborovic said:

Did a 375 mile trip yesterday, mostly highway, and the rattle is still stuck with the car ... now the main suspect is the exhaust pipe(s), that somewhere a part of it came loose and tumbles around as the car vibrates on bumps ... while I was under the car doing cleaning of the plastic covers under the floor, I've tried the movement of the exhausts system by hand, nothing obvious that would suggest that something is too loose, maybe I'll go to the exhaust specialist to take a closer look, it will be very funny if it is something simple (as such issues usually are)

Have you checked the boot door? I know my Superb had lots of noise from the back and it turned out it was the 2 plastic bases that the rubber stops hit as it closes we’re not adjusted properly. I am aware it effected the estate (combi) but I’m sure a hatch will be similar. Not sure if I explained that very well, I will take a photo tomorrow. 

[vborovic]

I know what you're talking about, but the boor is closed air-tight ... I think the rattle-maker has been located (the car is AWD) - the cardan shaft outer protection (don't know the exact term), the plastic pipe that protects the shaft itself, painted in red ... it is very loose, can easily rattle around its surroundings and is at this point the main suspect ... the question now is how to fix it into place, or, why it came off in the first place (and from what it came off).

 

[vborovic]

Can I get one of the members with a Superb II with 4x4 and some spare time to check something underneath the car for me, if would help in in tracking the issue with the central cardan shaft?

[vborovic]

Finally getting somewhere, on the previous picture, the red marked part of the shaft is what I can grab hold of while under the car (still not dismantled the exhaust to see the entire picture underneath), and I can rattle that around. So, the issue is actually in the propshaft centre bearing, which doesn't hold the shaft in place, and it rattles around. I'll try and order a used complete propshaft (with a lot less kms and in almost new condition), to avoid repairing just the bearing, and then still be left with a 10-year old propshaft (which at this point may be slightly deformed/damaged due to the loose position - even though nothing can be felt during the drive in terms of a failing 4x4 propshaft)

[zice]

rattles, esp. over speed bumps are a biatch.

i had two so far, solved them both: one was the driver door closing mechanism on the B pillar (that "U" latch thing), put some vaseline based lubricant (not silicone or WD40!) and it killed the noise. The other was my sheer stupidity of not folding the rear bench (the 1/3 behind the driver side) properly/fully back into its place

Edited 9 May, 2018 by zice

[Superb170]

On ‎09‎/‎05‎/‎2018 at 19:12, zice said:

rattles, esp. over speed bumps are a biatch.

i had two so far, solved them both: one was the driver door closing mechanism on the B pillar (that "U" latch thing), put some vaseline based lubricant (not silicone or WD40!) and it killed the noise. The other was my sheer stupidity of not folding the rear bench (the 1/3 behind the driver side) properly/fully back into its place

I use Vaseline as well on the latches from time to time and does the job, although my wife thinks I'm nuts driving around with a tub of Vaseline in the boot!!

[TheRobinK]

2 hours ago, Superb170 said:

although my wife thinks I'm nuts driving around with a tub of Vaseline in the boot!!

 

Better than having vaseline on your nuts and being left in the boot.