Soft brakes/ loss of brakes

[skos]

Soft brakes/ loss of brakes

Here is an interesting one.  Lately while pulling out of the garage and applying the brake I have only about 10% braking power.  I have to apply very hard to stop.  It is like my brakes were wet.  I also have a very small decline on my driveway so I am not building up any speed.

This is very random and only happens maybe once of month while baking out of the garage.  It is only while baking out of the garage.  Once I get going my brakes are fine and I have no issues until it happens again.

Any ideas?  I check the pads on all four wheels, I still have plenty of material left.  I checked the brake reservoir and it is full.

[dav]

I have had the odd problem with brakes in the last 6 weeks as well. Not the same problem as yours.
Have you any idea when the brake fluid was changed? You say brake reservoir is full but if brake fluid older than 2 years that may be your problem.Brake fluid does need regular changing as it absorbs moisture thus making the fluid less efficient.
Doesnt sound like you have any external leaks and you say problem is only intermittent.

[sgould]

It sounds odd.  I can only think that the disc pads are not seating correctly somehow.

Are the springs in the right place?  Are the discs corroded?  Are the pads and discs well worn and snagging on the small ridge that forms on the edge of the disc? 

All a bit vague, I'm afraid.  But I can't think of any problem with the brake operation that's different going forward and back.

Unless it only happens after an overnight park and you have a very slow leak in the servo.  Does it make any difference if you let the engine tick over for longer before you start to move?

[Guyver1]

Bit of a pain to do, but try removing the pads and press the pedal to move the brake piston out, not too far though, then give the piston a good scrub with fresh brake fluid using an old toothbrush.

I had a similar thing happen on my last motorbike, crap brakes when moving very slow but they felt ok at higher road speeds, once all the pistons where cleaned the brakes were superb

Not sure how many cylinders are on the car but I'd got 12 of the little buggers on the front of the bike

[Saabman]

I'd also be checking for a servo problem from the description

[Max Headroom]

Sounds exactly like air in the system. Check for any leaks under the car particularly at the wheel cylinders. If fluid can get out air can get in

[v6ragtop]

You should get your servo hoses checked as a small leak may cause this type of problem which ultimately will show as a check engine warning