2010 Mazda 6 Brake Pedal Issue

I have a 2010 Mazda 6 with an unusual issue. When I step on the brake pedal it resists for a quick moment then seems to “collapse” and go to the floor. The resulting braking is affected, but almost unnoticeable. When I quickly release the pedal and re-apply pressure the pedal doesn’t quite “collapse” as bad, but still is not as resistive as it normally is.



I have taken it to the dealership three times for this issue and they can find nothing wrong with the car, the brake pedal or brake systems. It doesn’t happen all the time and is not weather or outside elements specific.



Any help in figuring out what this is would be great!

sounds like a failing brake booster or master cylinder. need to find the magic condition to make it happen. Or, find a way to leave it with the dealer for a while.

This sounds very, very much like a defective Master Cylinder. The car is unsafe to drive this way. I’d recommend that you look at the booket that came with your woners’ manual. There should be contact information to push the problem “up the chain”. Also write to these people
www-odi.nhtsa.dot.gov/ivoq
They’re the government agency that tracks safety problems and forces safety recalls.

And document everything. Make sure you keep your copies of the shop orders and all correspondence.

And check up on your state’s “lemon laws”. You may have enough to get them to replace your car with another for free.

yes to calling Mazda USA HQ
yes to contacting the NHSTA
and yes to checking http://www.lemonlawamerica.com/ and finding out what recourse you might have with this issue

This isn’t that unusual. Failing master cylinders often do this. This is an unsafe condition, so you need to get it fixed right away. If you absolutely must drive the car, be mentally prepared to downshift your transmission immediately and then use the parking brake. Is there another dealer you can try?