Reduced efficiency on brakes

[Ditch]

As part of the deal on my car , a 2012 c220 estate ,the B3 service is a freebie. It involves amongst other things changing the brake fluid.

Upon return nothing amiss until I drove it. In a word the brakes don't work as well as they did when it went in !!!

No other brake parts were changed or altered just the fluid changed. I now have greater travel on the pedal both free and to brake, it has a softer almost but not quite spongey feeling about it. First application at 15mph after pulling off the drive was wtf !

Just not as good, would probably pass mot if required but as they were previously pin sharp I'm not happy. Very hard to put your finger on it.

I would guess air in the system but as they either pump or pull the fluid through how on earth can they get it wrong ?

Does anyone know of any "be careful" bits in the process do donts etc in their service manual ?

I'm thinking maybe pedal left on the floor , abs not cleared properly or whatever.

All suggestions gratefully read.

Taking it back tomorrow

 

[190]

Sounds like they really need bleeding again.

You could try wedging the pedal down and leave it it overnight. It's almost a routine procedure on some motorcycles and I did try it with success on a car once.

 

[Ditch]

Cheers. Never had to do that before lol. I do agree with re bleed required. Last time I experienced this was on a seat Toledo when I got air in the abs unit.

 

[Ditch]

Got up this morning and gone to use the car and it's improved. Still not back to what it was but almost as though it's self bleeding !!!

Confused.

 

[grober]

Brakes are something you want spot on. Despite any improvement get the garage to check it out. If the B3 service was free maybe they rushed it through or the apprentice got the job?

 

[Ditch]

Agree on all points. Sitting enjoying their coffee as I type

 

[rorf]

You do not mention what dealer it is - Mercedes or some other franchise.

They bled the brakes, they must fix it.

Reason I do my own services, can't trust anyone these days.

 

[Ditch]

I wasn't losing the plot. Merc dealer immediately agreed it didn't feel right , didnt suggest it was worn discs pads etc.

In fairness to them they did a cracking job this morning and thoroughly rebled the system which slightly improved things further. A quick diagnosis and input from a member of staff who had seem similar once before led to the idea that the fault lays either within (air ingress) or is the electronic stability/traction module (whatever merc call it) .

the brakes are working well, easily serviceable and safe, going back early next week for the full job, all on warranty or follow up.

 

[momomo]

I wasn't losing the plot. Merc dealer immediately agreed it didn't feel right , didnt suggest it was worn discs pads etc.

In fairness to them they did a cracking job this morning and thoroughly rebled the system which slightly improved things further. A quick diagnosis and input from a member of staff who had seem similar once before led to the idea that the fault lays either within (air ingress) or is the electronic stability/traction module (whatever merc call it) .

the brakes are working well, easily serviceable and safe, going back early next week for the full job, all on warranty or follow up.

Hi Ditch

Many thanks for pointing me over to your thread. Glad to hear you managed to get the issue solved and brake pedal how it should be.

Just to be clear, the issue was down to what the staff member suggested- "the fault lays either within (air ingress) or is the electronic stability/traction module (whatever merc call it) . "

Is this correct? Or was it just a case of a proper re bleed?

Appreciate your input.