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a_Y
04-02-2016, 06:44 PM
i am plagued by a soft brake pedal problem that I can't solve and want to see if any of you guys can help. The brake pedal is soft and I mean really soft even compared to other e46 m3's or normal BMWs. I have bled the system, changed fluid, bled the system again. I then thought it was a vacuum leak so I had vacuum hoses and brake booster changed. I am still having this problem and it won't go away. Next thing I am going to try is having the master cylinder changed.

Any one have any clue as to what this problem may be?

cslsuperfan
04-02-2016, 08:18 PM
i am plagued by a soft brake pedal problem that I can't solve and want to see if any of you guys can help. The brake pedal is soft and I mean really soft even compared to other e46 m3's or normal BMWs. I have bled the system, changed fluid, bled the system again. I then thought it was a vacuum leak so I had vacuum hoses and brake booster changed. I am still having this problem and it won't go away. Next thing I am going to try is having the master cylinder changed.

Any one have any clue as to what this problem may be?

A_Y

you should be able to get a seal kit for the master cylinder

If there's no obvious fluid leaking onto the floor then it could be fluid getting back past the master cylinder piston under braking. Not a common fault but worth a look.

glendog74
04-02-2016, 09:59 PM
i am plagued by a soft brake pedal problem that I can't solve and want to see if any of you guys can help. The brake pedal is soft and I mean really soft even compared to other e46 m3's or normal BMWs. I have bled the system, changed fluid, bled the system again. I then thought it was a vacuum leak so I had vacuum hoses and brake booster changed. I am still having this problem and it won't go away. Next thing I am going to try is having the master cylinder k

Any one have any clue as to what this problem may be?

You need AP brakes :thumbs:

a_Y
05-02-2016, 05:38 AM
A_Y

you should be able to get a seal kit for the master cylinder

If there's no obvious fluid leaking onto the floor then it could be fluid getting back past the master cylinder piston under braking. Not a common fault but worth a look.

I have ordered a new master from the dealer today.. let's see if this works...

You need AP brakes :thumbs:

next step! i need to get this sorted before getting that!

billyboysm3
05-02-2016, 09:10 AM
Did you bleed the brakes or did BMW ?

CraigMillwardCroft
05-02-2016, 09:12 AM
Did you bleed the brakes or did BMW ?

Who's at fault :whistle:

a_Y
05-02-2016, 11:54 AM
Did you bleed the brakes or did BMW ?

BMW both using a power bleeder and doing it manually

billyboysm3
06-02-2016, 12:22 PM
I reckon they have done it wrong. You and a mate need to do it and really stamp on the peddle pushing it all through. BMW always make it limp.

billyboysm3
06-02-2016, 12:29 PM
They have done it correct but not to anyone's liking

a_Y
07-02-2016, 09:21 AM
I reckon they have done it wrong. You and a mate need to do it and really stamp on the peddle pushing it all through. BMW always make it limp.

Can you kindly explain what is the correct way? Thanks!

a_Y
08-02-2016, 01:06 PM
I recently saw on m3forum about a method called the TIS method of bleeding the brake and abs/dsc system. Do you guys know anything about this method that you can share? Thanks!

a_Y
05-03-2016, 06:12 PM
Im glad to say that the brake issue has been solved after replacing the master cylinder! Cesil all healthy now!

m3cslarmo
08-03-2016, 07:11 PM
hi all,,my first post on here an its off topic but i can't start a new thread yet :-(,,I've just had an inspection 2 on my csl and everything was marvelous apart from,,and i quote "a slight groan from the dif",just wondered if anyone else has had this and what work is involved
thanks in advance