If the brake pedal suddenly sinks to the floor – what to do?

If you asked most people what kind of nightmare car problem scenario they fear the most, they would probably talk about some problem with the brakes. It could be anything from the brakes suddenly not being as effective as they should, to the brakes failing completely. A real scenario people face is the brake pedal getting too spongy and loose and then pressing the brake all the way to the floor to get the reaction they need.

In today’s blog, we take a closer look at this type of brake pedal problem, what causes it, and what it means for your vehicle and your driving.

If the brake pedal suddenly sinks to the floor – why?

Brake fluid loss

The first thing that should come to mind when you have this brake pedal sinking to the floor problem is that your hydraulic brake system Now it’s running out of brake fluid. Most likely there is a brake fluid leak somewhere as the fluid shouldn’t be disappearing at this point. Check under your car when it’s parked to see if there might be any fluid build up there. Brake fluid has a yellowish tint.

Defective master cylinder

Another possible cause of pedal problem is found in a faulty master cylinder. The master cylinder, as its name suggests, plays a central and critical role in the overall functioning of your hydraulic brake system. It is actually the master pump that sends brake fluid through your brake lines under pressure which in turn triggers the brake calipers to push the brake pads firmly against the rotors to slow down the vehicle.

See also  How long does it take to get new tires?

The most common master cylinder failure is seal wear, which can occur due to age, or due to the presence of contaminated brake fluid. Any situation can cause the pedal to sink into the floor. You may also notice this in conjunction with your vehicle generally not being able to hold itself in place without constantly slamming on the brakes.

ABS Unit Leakage

The vast majority of cars on the road have ABS these days as it is not an innovation. Your car’s ABS system uses a variety of sensors and control modules to detect how much brake fluid is currently in the master cylinder reservoir. The ABS system itself runs on hydraulic brake fluid, so drops in reservoir levels that go undetected will also contribute to the sinking pedal problem. Even worse, you might not get any notice about it.

Your own driving style

Finally, the brakes may be left in the condition they are now due to the vehicle owner’s driving style. If you’re a typically aggressive driver who likes to step on the gas hard and then brake just as hard, then you’re putting the brakes – not to mention the engine and transmission – in a cycle that will wear out major components faster. When you use the brakes too aggressively, the brake fluid gets hot and dilutes, which means you need to increase the pressure to make the brakes work harder.

Reducing your level of aggression when driving will invariably solve this problem. Be softer on the brakes and try to break the cycle of rapid acceleration and hard braking. Not slamming on the brakes when going downhill will also help preserve brake components and prolong brake life.

See also  Head Gasket Vs Valve Cover Gasket

Different Braking Systems

We should all make more of an effort to know how our brakes work and even what kind they are. If you were put on site now with no chance to check, could you say for sure if it has disc or drum brakes? If you know you have both, do you know which are in front and which are in back? Could you explain the difference between disc and drum brakes?

Drum and disc brakes – the difference

These two types of brakes use the same basic braking principle, which is to apply friction to the wheels to slow them down. They just do it in different ways. Drum brakes are arguably the simplest, consisting of a drum, a series of wheel cylinders and brake shoes. When pressing the pedal, the shoes are forced against the inner surface of the brake drum by the cylinders, creating friction and slowing the car.

if the brake pedal suddenly sinks to the floor

Brake discs are the more modern option and are made up of a more complex assembly that includes the brake rotor, calipers, brake pads, bearings and much more that together make up the brake assembly. Using brake fluid hydraulics, pressure travels from the pedal to the brake pad with greater force. The pad is housed in the caliper, which closes on the rotor with significant force to bring intense friction to slow the vehicle down.

What to do if the brake pedal suddenly sinks to the floor

If your pedal is sinking into the floor and you’re getting little reaction from the brakes, then the first thing you should do on the road is put the car in a lower gear and then slam on the brakes. Some think it’s best to put the car in neutral, or even turn it off. Not really. Keep calm first, then downshift before hitting the brakes.

See also  What is random direction? Pros and cons of this technique

Once you’ve restored balance and feel more stable, you should seek help from your mechanic. Your car is not safe to drive when the brakes aren’t working as they should, even by a small margin. So even if your pedal sinks to the floor but you basically get the same amount of braking you would expect, you still need to get a mechanic to take a look at the brakes. The unavoidable fact is that the brake pedal must not sink to the floor.

It is extremely likely that your brakes have been neglected and are in need of serious maintenance and repair. So make it your first priority to serve them.

Go home

Leave a Comment