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View Full Version : Knocking noise from left front suspension - Audi A4 B8 2010



JacobMY2010
30-08-2015, 06:52 PM
Hi All.

My car is Audi A4 2010 (60k miles) Estate S-line .

Few weeks ago I have noticed knocking noise from the front passenger(left) suspension and since then couple of mechanics looked at it and checked for playing (by using a metal bar) all arms and surrounding parts plus tightened subframe bolts and couldn't find anything wrong so far - no knocking noise.

The knocking noise happens when moving slowly over uneven pavement such as moving about 5-10 mph in a parking , sometimes knocks while turning on low speed(parking) but never when turning stationary , sometimes this can be simulated by going forwards and backwards (knocking once at each change of direction), knocks when you accelerate and decelerate at low speed.

On smooth roads it never makes the noise even at low speed (except when changing gear from 1 to 2 when engine is released then lifted again). Once the car is moving more than 20 miles per hour or so it's gone or at least I never hear it.

Summary:

1) on uneven roads while driving and turning - it knocks quite alot but only on small bumps , nothing on big speed bumps
2) accelerating and decelerating at low speed - it knocks once when accelerating and second time when decelerating
3) going forwards and backwards - knocking once at each change of direction



Not sure if weather condition got any influence(when its hotter it knocks more and louder) or part temperature is related on it but I have tried to reproduce the noise on couple of mornings and couldn't get any noise but after driving the car for 20 mins I could hear it just then drove it for another hour and noise was clear and loud.

Don't know really what to do next , do anyone knows any tests to perform which could eliminate good parts? Thanks for any advices.

Please Help!!! ^^

fat controller
30-08-2015, 09:54 PM
Not being funny, but rather than the noise being from your suspension/steering, could it be more related to when power is applied or released? I am wondering if you might be having early DMF symptoms.....

MiniMental
30-08-2015, 11:29 PM
Unsure on brake setup of B8 but if it's anything like earlier vag cars, could be brake caliper knocking? I had this issue on my b5.5 Passat even with spring installed on callipers. New springs fixed it. Just a though... Try rocking it fast when stationery (and cold, definatley don't do it when hot...)

If not, I'm back on the bench.

Mini

JacobMY2010
31-08-2015, 10:05 AM
Not being funny, but rather than the noise being from your suspension/steering, could it be more related to when power is applied or released? I am wondering if you might be having early DMF symptoms.....

Hopefully not as my DMF and Clutch has been replaced year ago on 50k :o

For me and for two mechanics who looks at it the noise is coming clearly from left front (wheel area) but you never know so thank you for idea


Unsure on brake setup of B8 but if it's anything like earlier vag cars, could be brake caliper knocking? I had this issue on my b5.5 Passat even with spring installed on callipers. New springs fixed it. Just a though... Try rocking it fast when stationery (and cold, definatley don't do it when hot...)

If not, I'm back on the bench.

Mini

When I have mentioned brake calipers to my mechanic he said that it wouldn't knock as loud as it is at the moment(he thinks it got to be something bigger) , he had quick look but couldn't see anything wrong , but thank you for an idea , next weekend I'll ask him to take caliper off and look closer on it.

MiniMental
31-08-2015, 01:04 PM
I thought that. My Passat sounded terrible. Took months to sort it out and I noticed if I pulled/pushed it hard and fast I could replicate the sound. New springs sorted it mind and it didn't move much. Just a mm or so.

Good luck :)
Mini

JacobMY2010
15-06-2016, 01:37 PM
After many months of waiting for the noise to go louder to be able to find out where exactly the noise was comming from instead of replacing part by part , new ex audi mastertech started at my work place asked him for a quick testdrive to see maybe he could find out what the noise is.... 5 minutes after the noise was gone. We found out that the noise was still there when bonnet was closed and gone when opened. Believe it or not but all he has done was WD40 few sprays on bonnet hinges and noise was gone /clap . Couldn't believe it was so easy. After he said it is very common when hinges are getting dry. / hurray

Boy
15-06-2016, 09:40 PM
That is a very useful tip. Thanks.

Sammy123
05-09-2016, 05:54 PM
After many months of waiting for the noise to go louder to be able to find out where exactly the noise was comming from instead of replacing part by part , new ex audi mastertech started at my work place asked him for a quick testdrive to see maybe he could find out what the noise is.... 5 minutes after the noise was gone. We found out that the noise was still there when bonnet was closed and gone when opened. Believe it or not but all he has done was WD40 few sprays on bonnet hinges and noise was gone /clap . Couldn't believe it was so easy. After he said it is very common when hinges are getting dry. / hurray

Sounds exactly like noise I'm getting, gonna try this soon !