Noise when braking

[Shay63]

Hi all,
My first post, hope someone can help.
When I brake there is a single sound coming from the front left of the car (2004 CLK 270 CDI).
It's a single tuck/tap sound. Doesn't happen on hard breaking or very soft braking.
Sometimes it happens as soon as I touch the brake pedal.
My mechanic has had several goes at finding it but he's beat! He's very good and I have used him for years.
Has anyone come across this type of problem before?
He's looked at the arms, ball joints etc etc but still cannot work it out.
Any help is greatly appreciated.

 

[brandwooddixon]

I was going to suggest castor arm bushes

 

[Shay63]

I've just checked with him, all that has been looked at. He's looked at this problem 3 times but cannot get to the bottom of the problem ‍

 

[LostKiwi]

Sounds like maybe a pad moving.

 

[bembo449]

Think LK is right , if it happens only on initial braking it suggests the pads are moving in the calipers

 

[Shay63]

Sounds like maybe a pad moving.

Thank very very much

 

[Shay63]

Think LK is right , if it happens only on initial braking it suggests the pads are moving in the calipers

Thank you

 

[umblecumbuz]

If, as you say, your mechanic is good, then he will have repeatedly checked the obvious suspects - the bushes and joints, such as those in the suspension, anti-roll bar, drop links, and he will have checked the caliper assembly..

Although pad movement can cause the symptoms you describe, I have seen two other possible causes. The top mount of the suspension strut can wear to the point that it 'clicks' when the car is first used after a period of inactivity, and a cracked suspension spring can also do this. A cracked spring is sometimes very hard to locate.

I recently had a Fiat Panda that gave out a similar mystery 'click' when first driven each day, and this was a semi-seized strut top mount. We searched repeatedly for the cause, and only when we noticed the top mount give a 'jerk' as the steering was turned did we suss it.

 

[Shay63]

If, as you say, your mechanic is good, then he will have repeatedly checked the obvious suspects - the bushes and joints, such as those in the suspension, anti-roll bar, drop links, and he will have checked the caliper assembly..

Although pad movement can cause the symptoms you describe, I have seen two other possible causes. The top mount of the suspension strut can wear to the point that it 'clicks' when the car is first used after a period of inactivity, and a cracked suspension spring can also do this. A cracked spring is sometimes very hard to locate.

I recently had a Fiat Panda that gave out a similar mystery 'click' when first driven each day, and this was a semi-seized strut top mount. We searched repeatedly for the cause, and only when we noticed the top mount give a 'jerk' as the steering was turned did we suss it.

Thank you so much for that, I’ll share it with him.

 

[joderest]

Could well be the pads.
Experience, i changed the front discs and pads on wifes mini, the pads were, erm, an unknown make, but came with the discs. She complained that backing off the drive she heard a clunk, then when she stopped at end of road another clunk, after that she said she did not hear anything until the same the next day.
I checked it all over and could find nothing incorrect, but for piece of mind i went out a bought a set of MINTEX pads and fitted those.
The issue was gone and never returned. I could see no difference between the pads, it must have been very small.

 

[Shay63]

Could well be the pads.
Experience, i changed the front discs and pads on wifes mini, the pads were, erm, an unknown make, but came with the discs. She complained that backing off the drive she heard a clunk, then when she stopped at end of road another clunk, after that she said she did not hear anything until the same the next day.
I checked it all over and could find nothing incorrect, but for piece of mind i went out a bought a set of MINTEX pads and fitted those.
The issue was gone and never returned. I could see no difference between the pads, it must have been very small.

Thank you very much for that.

 

[Shay63]

Hi all, thanks for all your help.
It was the brake pads as well as the original callipers had stuck.
Cost a pretty penny but car is great now.
One other problem, I need an SRS mat seat emulator for my 2004 CLK 270 CDI.
Anyone successfully bought one and used it?
All advice greatly appreciated.

 

[LostKiwi]

Hi all, thanks for all your help.
It was the brake pads as well as the original callipers had stuck.
Cost a pretty penny but car is great now.
One other problem, I need an SRS mat seat emulator for my 2004 CLK 270 CDI.
Anyone successfully bought one and used it?
All advice greatly appreciated.

Have one in our 210.
Essentially the emulator allows the airbag to deploy in an accident even if the seat is unoccupied.
Simple to fit and been fine for 2 years but beware there are several versions

 

[Shay63]

Thanks very much, I've already returned two KDL Tech ones, they do not do 2004 CLK ‍

 

[Shay63]

Hi All,
My mechanic has tried the new switch, please see attachment.
The front seat señsor malfunction has gone and replaced with SRS Restraint system defective Drive to Workshop.
Also, the front passenger will not extend
Thank you?

 

[Shay63]

BTW, the red SRS sign is now flashing and not constantly on.