One episode of not being able to push brake pedal to the floor

toyota
matrix

#1

I have an '03 Toyota Matrix with 98 thousand miles on it. A week ago Friday was the 1st or 2nd day of sub zero weather here. I walk to work so don’t use my car all day. That night I went out doing errands at around 8PM. After about 15-20 minutes driving in my car I was on a side road doing about 40, I stepped on the brakes and couldn’t get the pedal to push down and the brakes wouldn’t work to stop the car. I pressed two more times with my foot and the same thing happened. The pedal wouldn’t press down and the car had no braking action. I let the car slow with my foot off the gas, tried it again and the brake worked like normal. The foot pedal pressed down and the brakes worked. I was near the store I was going to shop at, so I parked and went in for about 20 minutes, then drove home with no problem. I took it in to the Toyota dealer and they could find nothing wrong with the brakes. I later took it in to another place and they also could find nothing wrong. I have been using the car sparingly as I am a little nervous, but things are working like normal. Do you know what the problem could be? Should I be nervous?


#2

@MarkCecil

If the pedal was rock hard, you have a vacuum problem

Vacuum brake booster
The hose going to the booster
An engine vacuum problem . . . not enough vacuum going to the booster


#3

The problem might also be with the vacuum brake booster check valve.

Tester


#4

OP metioned inop brakes. A vacuum failure would still allow non-assisted brake function…just more effort.

Maybe he’s got a coffee mug or something rolling around…

I’d recommend seeing how long vacuum is held after turning engine off.


#5

A bit of a stretch here, but is it possible that the brake fluid has absorbed so much water that some ice formed somewhere in the system and a brake flush would be in order here?


#6

I believe Keith is correct. Brake fluid absorbs water over time and IMO the fluid froze.
Have a shop flush the system with new brake fluid.


#7

It’s possible also that water splashed up and ice formed on something in the brake system which is normally supposed to move freely, but got frozen in place b/c it is so cold, like the caliper slides, which locked the brakes up. I’ve lived in a fairly cold climate before, never seen or heard of that happening though. The truck I drove then (& now) has drum brakes. The moving parts of disc brakes are more exposed to water splashes, maybe that has something to do with it.

OP should of course – until this is resolved – test the brakes several times upon leaving home, and to immediately return to driveway and park the car for the day if they aren’t working 100%. Besides the above ideas, esp the one to have a mechanic verify the brake booster function is working correctly, the OP should try the emergency brake, see if that stops the car when this happens. Could provide a clue at least. And as mentioned above, make sure there is nothing obstructing the brake pedal.


#8

A vacuum issue wouldn’t surprise me. Unless someone already knows what it feels like to drive without power assist, then feeling could easily be interpreted as “no braking” - when it was really just requiring a whole lot more force than normal. I also wouldn’t rule out the coffee cup rolling around though.


#9

Are you sure you didn’t have your left foot under the pedal?