Hi,

The brakes were operating fine until 4 weeks ago then when I on my way home and used the brakes the pedal almost dropped to the floor, the car still stopped. This happened all the way home - I was driving carefully. Checked for leaks but none found and fluid level did not look like it had dropped.

 

My local garage had a look the next day but by then it was all working correctly again, they road tested it for about 10 miles but the fault did not appear. Then it happened again last week, no leaks found and I bleed all the brakes using about 1/2 litre of fluid. At the weekend the brakes were working fine but today it started again.....

 

Any ideas, car has ABS.

 

Thanks

Softly going to the floor ?

 

I'd be surprised if yours and mine isn't the only one, I thought I read this could be a common fault but it would be useful it someone could definitely rule out that this is not related to brake seals etc.

 

I've had my car from new and I'm sure I've had this for most of its ( 124k) life and even discussed this behaviour with someone else with a different car and he mentioned someone else with a porsche also that said they shared similar behaviour.

Might have something to do with the servo thingy, that adds more power to your braking and there is a known issue with it and it can suddenly go hard as a fault ? If that happens you apparently need to have the vaccuum thingy checked. I'm helpful here aren't I lol. Whereas a techie explanation when you need one.

I would scan the ABS controller for any fault codes.

 

SN

Can you 'pump' the pedal, and regain a solid pedal temporarily?  Likely a tiny air leak, hard to find - bet it's on the front caliper somewhere..  Look for a tiny wet bit.

The pedal drops quickly, not softly to the floor, and if you pump the pedal it regains the solid feel. The idea of a tiny air leak seems odd - if the fault occurs once left overnight the pedal is ok again.  I will investigate scanning the ABS controller.