Q: The brake pedal goes all the way to the floorboard

asked by on

Two times in the same day the brake pedal went all the way to the floorboard. One of those times I was fortunately at a stop sign; the second time, I was at an almost-complete stop. This is so dangerous and I am scared to drive my SUV - what if it happened and resulted in an accident or injury. I have been to the dealership and I was told that the brakes are in proper working order and that they could not replicate the problem. They also told me that my 2013 model is equipped with an entirely different brake assembly than the prior years’ models, which had a verified brake-booster problem. From what I have observed, I am considering that there is a problem with the hydraulics in the master (booster) cylinder. In your professional experience, what do you think is causing the brake pedal to go all the way to the floorboard?

Hi. Your issue could very well be due to a faulty master cylinder. A fault in those particular model master cylinders have been experienced by QX56 owners in which air will seep into the brake fluid through the master cylinder. This is a difficult fault to find because the master cylinder is not electronically monitored. A trouble code will not develop for this component.

I suggest to have the braking system inspected by a certified technician. Be sure to inform them of the potential master cylinder fault. 

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. The brake pedal goes all the way to the floorboard

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Bad instrument cluster

With a reoccurring issue like this, you can almost guarantee that another malfunction is causing the failure. If this cluster has failed, you will end up needing another one. But do not replace it until you know what the main...

Q: How Do the Cylinder Numbers Impact Vehicle Performance and Reliability?

Engines in today’s automotive vehicles come in different sizes and number of cylinders depending on the vehicle size and weight or the work the engine is expected to do. The engine may also be used for performance or for better...

Q: Lost all transmission fluid near radiator overnight 2004 GMC Sierra

Hello - there are fittings at the radiator where the transmission oil lines go into the radiator side tank. Perhaps one or both of these fittings came loose, or broke - leaking fluid from that point? Gravity would do the...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...