Suddenly the brakes got weaker

[Iaitoo]

The braking power of my car hasnt always been very good. But yesterday they got really bad. Drove to work with no issues. On the way home they were really bad. The car stops, but dont think I can emergancy brake anymore. What could it be since it suddenly became that bad? If it was pads it would be gradually worse..

[powerandtorque]

Is the servo assistance working? If not, the pedal will be very heavy and it'll be difficult to generate significant brake effort.

[Iaitoo]

Pedal is not heavy at all. Can push it all the way down if I want to servo is also ok.

[Eeyore]

If you can push it all the way down to the floor it would suggest that the circuit is broken i.e. its leaking fluid somewhere.
If its heavy and it feels like there is no assistance then a vacuum line may have become disconnected somewhere.

I would put the car somewhere with a solid light floor and then pump the brakes several times and see whether it drops any fluid. Also check the master cylinder in the engine bay as it may not make its way onto the floor.

[Iaitoo]

Thanks for the advice. On easter vacation atm, hoping I can drive home from where I parked the car last night Tried pumping the pedal after I parked the car and it got really hard like normal. Would it do that if it was a leak?

[powerandtorque]

Generally speaking, a fluid leak will show by holding a constant hard pressure on the pedal - if it creeps down to the floor, there's a leak.

[Poodle]

Two options: If your pedal sinks with maintained pressure you've got a leak in the circuit. If the effectiveness of the brakes varies and feels spongy then it needs a new master cylinder.

Either way i'd strongly advise against driving it until you fix it, as either of those problems are likely to become a lot worse in a very short space of time - i speak from experience when i say the brake pedal dropping to the floor with no effect on the motorway exit sliproad sucks balls.

[Eeyore]

Yeh my experience of running out of fluid from a leak was that i came up to a roundabout and slowed and thought it felt a bit weak, pressed it again and nothing happened at all. Had to use the handbrake to stop from about 40 which was exciting... from noticing it was weak to no brakes was probably under 20m or about 5 seconds.

[Iaitoo]

Drove it home today, and it is constant. Pedal feels ok. Gonna check the brake fluid levels tomorrow Don't want to experience what you did!