Brake pedal going to the floor
The brake pedal is going to the floor.
Experienced mechanics share their insights in answering this question :
The brake pedal pushes on a rod that goes to the master brake cylinder. This, in turn, sends brake fluid to all of the wheels through the lines to the brakes at each wheel. If your pedal is going to the floor, and your break fluid is low, then you likely have leak in a line, or at a wheel brake caliper. If the brake fluid is not low, then it’s likely that the master cylinder is leaking internally and needs to be replaced. I would recommend having a mechanic, like one from YourMechanic, diagnose the cause of your brake pedal going to the floor, and recommend the best path to repair.
How to Identify and Fix Common car Problems ?
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When brakes are not as responsive as what they should be, or if the brake pedal “sinks” down to the floor, this is a possible indication of a braking system leak. It could be a brake fluid leak, or a brake hose air leak.
A worn or malfunctioning master cylinder. If the master cylinder isn`t performing as designed, it may need to be replaced. Defective replacement cylinder. If, after the master cylinder has been replaced and the system has been bled, and still your brake pedal goes to the floor, the new master cylinder may be defective.
If the brake pedal sinks to the floor when the engine is running then there may be a problem with the brake booster.
Brake System Leak
Unresponsive brakes or the `brake pedal goes to floor` symptom is a possible indication of a leak in your braking system. With a leak, an incorrect amount of hydraulic fluid will flow through your brake system— hindering your braking ability. A brake system leak could stem from many sources.
Air in the brake line(s) is the most common cause of a soft/spongy brake pedal. If air gets into the brake lines, it can prevent brake fluid from flowing properly, causing the brake pedal to feel spongy or soft. If the brakes are soft or spongy, this is a good time to change or flush the brake fluid.
If you have a stiff brake pedal and the vehicle has a vacuum pump or hydraulic brake booster, some common issues could be a missing serpentine belt, a failing electric pump, or low power steering fluid.
With power brakes, the pedal should stop 1 to 11⁄2 inches from the floor. (If you don`t have power brakes, the pedal should stop more than 3 inches from the floor.) If your vehicle has power brakes and stopping seems to take excessive effort, you may need to have the power booster replaced.
The classic symptom of a failing master cylinder is a brake pedal that “dives” or sinks slowly to the floor while pedal pressure is being applied. Another sign to look out for is any leaks around the master cylinder. If a seal is worn out, it may leak past the seal and onto the pushrod that attaches to the brake pedal.
When your ABS system malfunctions are can also cause a spongy brake pedal. Your ABS system is designed to allow the driver to maintain more control of the car in a high-speed stop.
The classic symptom of a failing master cylinder is a brake pedal that “dives” or sinks slowly to the floor while pedal pressure is being applied. Another sign to look out for is any leaks around the master cylinder. If a seal is worn out, it may leak past the seal and onto the pushrod that attaches to the brake pedal.
If you have a stiff brake pedal and the vehicle has a vacuum pump or hydraulic brake booster, some common issues could be a missing serpentine belt, a failing electric pump, or low power steering fluid.
The most common reason for a soft brake pedal is simply air still in the system. The easiest way to diagnose this problem is to pump the brake pedal gently a few times. In doing so, the pedal should become firmer with each gentle press of the pedal.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Supportive bar attached to brake pedal interrupts proper braking process
ANSWER : It’s possible to have someone alter the brake pedal or adapt a brake pedal from a different vehicle. You may call around to some customization shops to see if anyone is interested in taking on the project. But first, I would try reaching out to the selling dealer with your concern – especially since it is a new model. Good luck.
Why is my brake pedal going all the way down to the floor?
ANSWER : If you are having to refill the brake fluid from it getting low and the brakes go to the floor means you have a leak in the brake system somewhere. You may have a broken brake line, leaking wheel cylinder or caliper. You should not drive the vehicle until the brake system is inspected and repaired from the leak.
Low brake pedal and anti-lock brakes are not kicking in.
ANSWER : The brake pedal is working to stop the vehicle, but there may be air in the controller unit causing the ABS brakes to not function. I recommend bleeding the brake system from the farthest location from the master cylinder to the master cylinder including the ABS unit. If the brakes are still spongy after a full bleed, then the controller will need to be replaced. If you need further assistance with your brake pedal being spongy, then seek out a professional, such as one from Your Mechanic, to help you.
Brake sensor is to sensitive causing brakes to flicker while driving. 2005 Mercury Montego
ANSWER : Hi there – your brake light switch needs a minor adjustment. It is adjusted too "tight" or close to the brake pedal lever, or possibly has failed. Adjusting/replacing it will eliminate this flickering problem. I recommend a brake light isn’t working inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.
Hard brake pedal and rear brakes locking up.
ANSWER : Hi. I will help you with this issue you are having with your 2001 Durango. Unless you bled the master cylinder, it is possible there is still air in the system. If you car is equipped with ABS, air could have also gotten trapped in the ABS modulator. If ABS equipped, a bi-directional scan tool would be essential to manually activate the ABS system to clear air from that segment of the lines while you are bleeding the system. It is also possible that in all of this work somehow the proportioning valve has been affected causing the desired pressure differential, front versus back, to get out of spec. Using a 2,500 PSI gauge, you can check the pressures at each wheel and that will definitely give you a clue as to which brake circuit is the issue (or both), whether the proportioning valve is working properly and whether the line pressures at each wheel are within spec. Should you need a second opinion, by all means feel free to contact YourMechanic for assistance and we will diagnose and repair the issue for you.
abs light on brake line broke have been replace I bleed brake line but brake pad still go to the floor now wheels lock up
ANSWER : Hello. If the brake pedal is going to the floor then that means that it is not building pressure. If the brake system has been fully bled and there is no air in it then most of the time it is a bad master cylinder or it can be caused by a bad ABS module. If the brake fluid was low and if air got into the system then the only way to properly bleed it is with a scan tool that would allow you to open and close the valves in the ABS unit. Air gets trapped in these easily if the brake fluid gets low. This can also explain why the brakes are locking up. I would usually use my scan tool to bleed the system out first before going any further. I would also scan the brake control module to see what it is reading as a fault. If there is no air in the system and if there is no prominent code then I would replace the master cylinder first. If you want to check out why your brakes are locking up, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.
Brake pedal goes 3/4 way to floor
ANSWER : Hello there. This is a more unusual problem, especially given the amount of parts you have replaced. In most cases, the pedal travel is due to either the master cylinder or the brake booster, sometimes both.
Given that these have been replaced, there may be other causes. The most likely fault that comes to mind would be that there may be air in the brake fluid system or one of the brake calipers could be stuck requiring extra travel to engage.
This can occur over time and brake fluid attracts moisture or from replacing the brake components. Some vehicles may be difficult to remove all of the air from when bleeding and require the vehicle to be bleed different ways. If the brake system was vacuum bled then it may need a mechanical bleeding to resolve the issue. If you would like to have this done, a certified mechanic can diagnose your brake pedal issue and determine what should be done next.
EPC light on 2004 Jetta. Code said brake switch faulty, but brakes lights worked. Replaced brake switch, now no brake lights.
ANSWER : Hi there. The first thing that pops in my mind beyond of what you have listed is perhaps the electrical harness attached to the brake switch. Perhaps the harness itself is damaged or you have an exposed wire, loose ground wire somewhere. You might want to have a professional mobile mechanic come to your location and complete a brake lights not working inspection to help you diagnose this issue.