A brake pedal should feel consistent. If it suddenly travels farther, feels spongy or slowly sinks under steady pressure, the braking system needs checking before the vehicle is used normally.
Air in the hydraulic system
Brake fluid is effectively incompressible, while air compresses. Air introduced during a repair, through a leak or after the reservoir has run low can therefore make the pedal feel springy. Correct bleeding matters, and some ABS systems require a diagnostic procedure to operate internal valves during bleeding.
Fluid leaks
A leak may be visible at a caliper, wheel cylinder, flexible hose, metal pipe or master cylinder. Fluid can also escape into a brake servo where it is not immediately obvious. Any unexplained drop in the reservoir level should be treated seriously.
Master-cylinder problems
Internal seals can allow pressure to bypass inside the master cylinder without a large external leak. A pedal that slowly sinks while constant pressure is applied may point in this direction, although a proper inspection is needed before condemning the part.
Mechanical movement
Excessive caliper movement, incorrectly adjusted rear drums, a distorted component or wheel-bearing play can push pistons back and create additional pedal travel on the next application. This is one reason a brake complaint should not be diagnosed from pedal feel alone.
What to do
If braking performance has changed suddenly, a warning light is on or the pedal approaches the floor, stop using the vehicle and arrange recovery. Pumping the pedal may create temporary pressure, but it is not a repair.
Capital Garage carries out brake inspection and repairs in Ruislip, including hydraulic fault-finding, calipers, discs, pads and related components.
Still not sure what is causing the problem?
Symptoms can overlap between several faults. A proper inspection and diagnostic process is usually cheaper than replacing parts based on guesswork.