2007 Mazda 5 touring auto tranny, 112,000 miles. Lask week went to stop at a light and pedal went almost all the way to the floor. I had normal braking at the bottom of the pedal travel I think. I asked around and everyone said it sounded like the master cylinder. So, I ordered a new one, which are very pricey for a pos vehicle like this, had it installed. Try driving it. Same thing, take it back and tell them to rebleed the lines. They did and I still have the same problem. There is no air in the system. The pads are only 6 months old along with fresh rotors. So, what is going on here? I've just spent $365 basically to have new brake fluid installed in my car. I normally do everything myself but haven't had the time to mess with this car. Also, I've never had any car give me this much trouble with brakes, or an entire list of other things as well. This is the first vehicle I've ever purchased new, and it will be the last based on the horrible experiences I've had with it. I don't know of anything else to check to cause such a long pedal travel. I've tried googling it with no results, only stupid questions like why do my rotors rust after sitting a few days, or how to change pads. Please help. Pretty frustrated.

 

Have the brake hoses checked (the part between the rigid brake lines and the brake calipers); chances are pretty good that one of your hoses is having an issue.

 

I actually forgot to mention that there are no leaks. I'm sorry. I did have this checked. I'm not familiar with the newer braking systems. Is there anything electronically that would cause my symptoms? It seems like since its a closed hydraulic system, then there shouldn't be an issue here. I will make time to go through the vehicle this weekend and post my findings. If anyone else has suggestions until then, please, voice them.

 

I wasn't trying to suggest a leak. When the brake hoses age there are several failure modes ranging from ballooning when the brakes are engaged to internal failures which obstruct the flow back up toward the master cylinder, and then require significant brake pedal travel before anything happens.

As for electronic, unlikely, brakes are still pretty much a pure hydraulic system.

 

spammers suck!!!

 

Is there a vaccuum controlled brake booster on the firewall? A defective one will cause this, especially if you do a lot of city driving (it would fail sooner with city driving).

 

If it were the brake booster, it shouldn't show a spongy pedal, but the opposite, basically really stiff brakes "hard to depress".

 

Hi there, I am new to this forum.

Around christmas 2011 I noticed that on my Mazda 5 Sport 2008 that if I stopped at a junction, holding the car stationary with the foot brake that the footbrake pedal would travel all the way to the floor in about 8 to 10 seconds, a bit concerning.

When I booked the car in with the main dealer for its service in January 2012 I brought this point to their attention and they said that they would investigate.

When I colected the vehicle they advised that I needed new front pads and discs due to wear but also they would replace the master cylinder under warranty.

When the parts eventually arrived the car was booked in and the work duly completed. The bad news is that on colection after completion of the works it now takes 2 to 3 seconds for the footbrake pedal to travel to the floor!

They have had the car back for 3 days this week to try and resolve the problem and apart from comparing the problem with another Mazda 5 I don't think they have touched the car. How can a new master cylinder be worse than the one they took out?

I am definitely not happy about this situation and wil contact MMUK on Monday.

Does any body have any experience or knowledge of this problem?

Regards

Infiltrometer

 

it is frowned upon in most forumns to hijack someone else's thread infiltrometer. anyways, still no luck with isolating this brake problem.

 

Ditto on checking the hoses, they get soft when old and can expand enough to REALLY change how the pedal feels when braking, although 5 years is really really odd if the are doing that, my trucks lines were 19 years old when I changed them and they were bad but still "working". Also cycle your ABS a few times, find a nice parking lot thats empty or a deserted road and get up to a decent speed and just slam the brakes, cycling the ABS will move fluid through it and should also purge any air in its system as well. If they didnt bleed the master correctly it will cause issues like this also, pumping the hell out of the brake when not moving can slowly solve this as well.