Knock driving me crazy!

[MyCarling]

Hi all. Been a member for a few months now and have never felt the need to post for help but I am well and truly stumped.

I have got a slight knock coming from the front drivers side. It not a loud knock and only happens while going over uneven road. I can hear it while going slow but obviously the faster I go the louder the engine gets so I no longer hear it. I have replaced pretty much everything I can think of and I don't know what to do next lol. Thank you for any advice you can give.

1998 a3 1.8t AGU
Replaced both wishbones
Replaced both wishbones bushes to poly
Replaced drop link arms
Replaced strut top mounts and bearings
Replaced anti roll bar bushes
Replaced both drive shafts

Additional mods
Oil catch can
K04-001
2.5 inch turbo back exhaust
Forge tip
Forge recirc dv

Remap as soon as this knocking noise is sorted and fmic installed

 

[Vex182]

Brake pads rattle? My rear ones were doing it for months before I found it.

 

[bazf]

Loose arch liner or belly pan?

 

[MyCarling]

Brake discs and pads been done. And there is no plastic belly pan on it. It sounds like a dull metal on metal. Its not far off the same sound as a wishbone bush that has gone bad?

 

[bentescort]

I recently bought a 2002 S3 and had the same knock over rough ground at low speeds.

After changing a few bits and pieces I discovered that the drivers side front shock was the culprit. Not only did it have no rebound left in it, the damper was rattling about in the shock body.

A pair of new dampers later and the jobs a good 'un.

Cheers.

 

[MyCarling]

Thanks mate. I will check that out when I get back from lodging. Cheers

 

[jojo]

Track rod and ends?

 

[MyCarling]

I have checked them and they are fine

 

[Grant-s3]

Have a look inside the engine bay incase anything is loose and knocking about. Then jack it up, remove the wheel and gently tap away with a rubber hammer and listen.

 

[ticketyboo90]

Wheel bearings?

 

[MyCarling]

I checked the wheel bearings last weekend and they are ok

 

[Gops]

I know this sounds obvious.. But is your wheel tight? Mine was slightly loose and I had exactly the same symptoms.. I have no idea how it came loose but I guess it worked its way loose somehow..

 

[Gops]

Ow and make sure the DV isn't hitting the strut brace.. Happened to me and drove me completely insane for months!!!

 

[MyCarling]

I haven't got a strut brace mate. Dv not hitting anything. All wheels are tight. I didn't change all these parts in one go so the wheels have been on and off numerous amount of times lol

 

[p1tse]

Cv boot? I had this before

Does it happen when turning at low speed?

Try putting it on full lock and have a look to see if cv boot is split, you'll probably see some gunk

 

[MyCarling]

Its not a cv boot mate. I have replaced both drive shafts with new boots. It happens when going straight and when turning

 

[jojo]

I have checked them and they are fine

I checked mine, and they were fine too! but on a Hunters 4 wheel alignment machine, it detected 0.1mm play on the passenger side steering rod!! Changed to a new one, and knocking disappeared.

 

[Tooks]

I would second what jojo said, my car was making very similar recently. All new dampers/springs/drop links/top mounts and roll bar bushes which I thought would sort it, but to no avail.

I replaced the track rods and ball joints more out of desperation than anything, and the noise disappeared. The stuff on there had sailed through the MOT a few weeks ago too, but must have been some play in there somewhere.

Not sure ultimately whether it was the track rod ends or ball joints, but I did notice a metal rattle sound when I tapped the steering rack arm on one side with a rubber mallet. When I do the same post change, there isn't a sound.

 

[MyCarling]

I will replace them then when I get paid next... I had just persuaded the wife to let me fork out on new shockers and coilovers lol

 

[Pubemammal]

I have this same knocking, also an A3 8L 1.8t. It has starting happening ever since I wound the coilovers down a couple of CM's. Let me know how you get on

 

[Pubemammal]

Also, when going very slowly and lightly putting foot on the brake, can you feel it through the brake pedal?

 

[MyCarling]

I dont feel it through the brake pedal mate

 

[RobinJI]

Yep, I'd second track rods/ends, I take it you did the lower ball joints along with the wishbones? Failing that it could be worth adjusting the steering rack.