Loud 'clunk/knocking' Noise When Braking.

[Wuk51]

I had the same prob on my e32 last month. Hard clunking at braking and turning. Worried me silly.

Took out the whole brake system, check recheck, steering linkage and refitted all ball joint from box to tierod ends.. Check bushing.. after a week sound still there..


Suddenly occur to me the only moving part not check was the simple arb vertical linkage. Instead of loosen, it was binding hard. And everytime it moves, it binds an made clunking noise. How did it get so tight? No idea. First ever i came across.

Changed it and mystery solved. Hope this help...

this story also happened to my e90.. changed steering rack...it solved but only for 1 month..now the loud sound came back...huhu

 

[Wuk51]

my e90 started making this knocking sound almost a year ago...

the sound appeared everytime i want to reverse parking, when u brake during turning, drive thru bumps and even if u had a uneven road...
since my car still under BSRI i've sent it to AB for checking and they can not figure out the faulty..so they started to change every part to find the source..last part changed is steering rack...the problem only solved for a month..then came back slowly..now the knocking sound back again...:smokin:

 

[parc]

Hi ... I experienced a few uneasy clunking sounds my self on my e32.

based on your description, i had a similar problem. During low speeds after just starting, i would have loud grinding noise (not clunking - sounded more like **Groong..Groong..Groong*) whevenever the brake is applied, and there would be kickbacks from the pedal, as if the pedal is kicking back...with vibrations.

I had it checked and the mechanic discovered that the culprit was the ABS sensor. what made it worse was that the warning system was somehow disabled and the bulb for the ABS warning system was removed.

Had the sensors replaced and the problem did not resurface.

However, after that episode, i had another problem which bothered me for exactly a year. i would hear loud metal clunking noise from the front right wheel whenever i hit uneven road surface. After multiple visits to the mechanic, I could not diagnose the fault or the source of the problem.

Suspension bushings were replaced, mountinfs changed and suspension checked and given the green light but the problem still persisted. One fine day it hit that the sound does not appear when the brake is applied, so I guessed it was the brake system on the front right wheel.

So with the new found theory, i headed to the mechanic and had the car checked.

The mech took off the wheel and started hitting the front caliper and true enough, i heard a familiar sound. The first mechanic who sorted the problem of my ABS sensors, missed out something.

The cuplrit was a missing clip on the front calipers.

So, if you have a grinding sound when applying brake with some vibration or feedback on the pedals, try looking at the ABS sensors. you may also want to see if the ABS light on your instrument cluster lights up when ignition key is turned on.

if you have loud clunking noise like to metal bits are colliding...then check your calipers.

I know we have two very different cars but no harm checking. Just a thought.

Cheers!

nice write-up bro...thanks for the info.
when the ABS warning shown in my OBC,this problem wont happen,no grinding or knocking sounds whatsoever.but whenever those warning lights went off,the grind n knocking sounds would appear...

my mech told me it was ABS/DSC module,because he already clean up n check all my wheel speed sensor..everything is ok according to him.if it is a sensor only.then ok la,im afraid it was the module..

same warning light as this: http://www.bmwclubmalaysia.com/forums/showthread.php?46799-ASC-and-ABS-light-stayed-on

thanks again to all.

 

[sudha]

So...it's the ABS module then...about the same what I went through.

It was a paing to figure what went wrong. In my case, when I had the ABS problem, i did not know what it was as the warning lights never came on - because the bulb was removed..

Once the sensor was replaced... it was all back to normal except for that caliper problem...pening bro....

Glad it you have solved it.

 

[parc]

Didnt manage to solve it yet,but atleast i knew the problem..can get a lot more infos if google 'abs kicked in early'. Due to check with mech tomorrow because my brake light warning start to light up,in red somemore..

 

[parc]

Didnt manage to solve it yet,but atleast i knew the problem..can get a lot more infos if google 'abs kicked in early'. Due to check with mech tomorrow because my brake light warning start to light up,in red somemore..

My abs kicked in early due to FL wheel speedvsensor problem..
Atleast its not the module..