Knocking noise/rattle from rear A3 Sportback (old thread)

batman2000

So, I have a problem. I bought a A3 (2005) from a Audi dealer and there is a knocking/rattle noise from the rear. Going over bumps, uneven surfaces. They had the car for a week and said they have checked it over. Initially they thought it was a loose rear shelf, if the shelf is removed and the boot mat the noise is still there, the multi-link suspension has been checked, bushings tightened, "everything" greased up. They though they might have it fixed, the fuel tank straps were tightened and cushioned. But it didn't work.Now if they cant find anything wrong after week, what hope I of getting it resolved. I drove a 2006 A3 sportback and there was not a whisper from the rear. The dealer told me, its a drivers car and noise from the back is normal. It's a pain driving on Irish roads which are not smooth and this noise from the back, PS the radio kinda helps.

Any ideas...

Should this be in the Tech Forum??

slimjimmc

I presume they checked the exhaust system isn't hitting off something?

batman2000

I presume so, it's one thing they didn't mention, also the noise seems to come from (or more apparent from) the passenger side. Which is the exhaust system. The fuel tank straps they put in would be on the drivers side

Moanin

I know it's fairly obvious but did you check something simple like the spare wheel / Jack is fully tightened to the frame of the car etc?

PaddyFagan

The other thing I'd get checked is the rear seat and the space around it - in my Golf Plus (there might be the same in the A3?) there is a bunch of openings that appear as the rear seats are folded that could allow junk/coins etc into the space under the seat.....

Paddy

slimjimmc

Two things which I've found have caused annoying rear rattles in my car,
a) folding rear seat not latched properly (seat rattles against the locking pin).
b) tailgate latch not pulling the tailgate fairly tight against the rubber seals. A simple adjustment of the latch plate sorted that.

Slidey

I got caught with a loose number plate on the back of a golf before, the rattle was driving me mental.

batman2000

Thanks all,

The Spare wheel and accessories were all removed, along with the shelf and boot mat and the rattle is still there,
I think the seats are all firmly in place.
Its a fairly loud knocking noise rather than rattle. but the boot/rear space is clear of "debris". I booked it back into Audi, if anything I think I has got worse with the driving over the past week.

Wait and see I hope !

Eamonn Kee

Hello there Batman. I have the same knocking its very annoying.
I read on one site that it was loose "shields" but what exactly the shields are I don't know. Hardly heat shields as they seemed to be plastic. Did you get yours sorted??

darrancampbell

Eamonn Kee wrote: »

Hello there Batman. I have the same knocking its very annoying.
I read on one site that it was loose "shields" but what exactly the shields are I don't know. Hardly heat shields as they seemed to be plastic. Did you get yours sorted??

The shield they are talking about I would say are the plastic shields on the two rear suspension arms, they have been known to cause rattles.

Supergurrier

It's me, let me out of the boot !

(Posted from my iPhone5 :pac:)

colm_mcm

I laughed at the 'drivers car' bit

Nothing constructive to add though

Eamonn Kee

darrancampbell wrote: »

The shield they are talking about I would say are the plastic shields on the two rear suspension arms, they have been known to cause rattles.

Hi Darren Thanks for that - I think you are right. They rattle quite a bit.

darrancampbell

Eamonn Kee wrote: »

darrancampbell wrote: »

The shield they are talking about I would say are the plastic shields on the two rear suspension arms, they have been known to cause rattles.

Hi Darren Thanks for that - I think you are right. They rattle quite a bit.

Hi Eamonn, if you want you can just remove them and it should have any side effects.

batman2000

Eamonn Kee wrote: »

Hello there Batman. I have the same knocking its very annoying.
I read on one site that it was loose "shields" but what exactly the shields are I don't know. Hardly heat shields as they seemed to be plastic. Did you get yours sorted??

Yep, Anti Roll bar bushings.

langdang

batman2000 wrote: »

Yep, Anti Roll bar bushings.

Audi dealer couldn't identify them as the source of the noise? Jebus...

furtzy

langdang wrote: »

Audi dealer couldn't identify them as the source of the noise? Jebus...

As above. The first and easiest thing to check.

gav4321

Recently bought 2007 A3 S line. The rattle in the back is driving me mad. Constantly rattling unless on a smooth tar road. Took it into a mechanic and he checked everything out. Said it all looks fine and that it might be the wheel. Changed wheel and it's still there.

I've tried everything, taking out th spare tyre, emptying boot - I've even driven around with back seats down to see if the rattle was anything internal but it's not.

Fingers crossed its something as simple as the suspension shields. Any idea if these can be removed yourself? Thanks

George Dalton

Rattling rear shock absorbers are a common issue on those S-Line A3s.

Before spending money on shocks check the cheaper mechanical options like worn rear anti roll bar links and also the clips break on the plastic covers underneath the rear coil spring supports on the rear suspension arms causing them to rattle. If those covers are the cause of the rattle then you can either replace them or just bin them, none of the other Golf based cars have them fitted and they don't serve much purpose.

Both of those issues should be easy to spot though so your mechanic would most likely have spotted if there was something wrong.

gav4321

George Dalton wrote: »

Rattling rear shock absorbers are a common issue on those S-Line A3s.

Before spending money on shocks check the cheaper mechanical options like worn rear anti roll bar links and also the clips break on the plastic covers underneath the rear coil spring supports on the rear suspension arms causing them to rattle. If those covers are the cause of the rattle then you can either replace them or just bin them, none of the other Golf based cars have them fitted and they don't serve much purpose.

Both of those issues should be easy to spot though so your mechanic would most likely have spotted if there was something wrong.

Thanks for the reply George.

Is there anyway I can have a look at this myself? I don't want to rush back to mechanic after spending a few hundred getting the car serviced a few weeks back.

As I said, take the car out on the motorway and there's not a sound out of it. Simply on asphalt roads, or any sort of bump as all and there's ratting. Seems to be coming from the back left tyre

gav4321

Hi,

Can someone explain how i can remove the supsension shields?

this might be the issue

thanks

George Dalton

They are just clipped into place.

gav4321

cheers thanks,

will get down and try and reef them off tomorrow.

gav4321

Hi.

Are you sure they just clip off?

Thanks

andredequeiroz

Hi! I have a similar issue in my Audi A3 8P3 2 door. The noise come from the rear, passenger side. When I get the wheel off, and started to punch the fuel tube, I found this king of sound from the videos below. But I don't know how to remove this tube to find what is making this crazy noise.

andredequeiroz

Why I can't post youtube videos here?

andredequeiroz

gav4321 wrote: »

Hi.

Are you sure they just clip off?

Thanks

George Dalton wrote: »

Rattling rear shock absorbers are a common issue on those S-Line A3s.

Before spending money on shocks check the cheaper mechanical options like worn rear anti roll bar links and also the clips break on the plastic covers underneath the rear coil spring supports on the rear suspension arms causing them to rattle. If those covers are the cause of the rattle then you can either replace them or just bin them, none of the other Golf based cars have them fitted and they don't serve much purpose.

Both of those issues should be easy to spot though so your mechanic would most likely have spotted if there was something wrong.

Video from inside my car. Couldn't stop the noise with my hands.
youtube /watch?v=1bEfAnJ52As

Video from outside, wheel off, punching the gas tube.
youtube /watch?v=QwNim-m5Cpc

Hope somebody could help me.