Brake Pedal very soft - goes to the floor

[django10000]

I'm trying to fix most of the issues with my car by myself, rather than taking it somewhere - but never really did any major mechanical work on my cars - aside from oil changes and the basic stuff. A little help would be appreciated with my current issue in which the brake pedal is pretty much hitting the floor before the car slows down. I checked the brake fluid level which is full to the top, there are no leaks that I can see, and the car's brakes were checked about a month ago. Any help would be very much appreciated...I'm sure I will have more questions in the near future. By the way, this a great site - I've learned so much just by reading the other threads you guys post. Thanks!

 

[minifridge1138]

If the pedal is soft, then you have air in your brake lines.
You should bleed the brakes and see if the problem goes away.
The proper bleed procedure can be found in any service manual, so I won't bore you with details (if you don't have a service manual, just ask for details and I will be more than happy to bore you).

Unfortunately, air in the brakes is only 1/2 the problem. The bigger issue is how did air get in your lines? It could be a leaking brake line, it could be that the calibers are leaking, or some sort of human error. You said the brakes were worked on a month ago. It is possible that human error got air in your brakes. That's what happened to me.

Bleed the brakes. When you do, the problem should go away. If they get soft again, that means you have a leak. If they stay firm, then enjoy the drive.

Good luck!

 

[Bob Chadwick]

If the pedal will come up when you pump it, you probably need a new master cylinder.

 

[pbcanney]

to add to the answer above,(minifridge1138) I would check the brake shoes as well. As they wear down, the plungers travel more, which in turn lowers your MC level.

just a thought.........

with all that go power, you need stop power

 

[minifridge1138]

I agree that there could be other issues. Master Cylinder, leaking calibers, worn sleeves, loose connection, faulty bleed valve, etc.

I said start by bleeding and see if the problem goes away. If the problem is just that air got in when the brakes were worked on, then anything else is a waste of money. If the problem does not go away, then we can work from there.

I had soft brakes a few months ago. The ONLY problem was that air had gotten in the lines when I was changing brake pads. The pedal would come up after i pumped it. The problem was solved for $5.00 worth of fluid and 20 minutes of work. That's a lot easier than spending money on replacement parts that aren't needed.

It is always better to find the problem and fix it, than randomly replace parts and hope the problem goes away.

 

[django10000]

Thanks for all the feedback - hopefully its the $5.00 solution you are referring to. I will try bleeding the brakes this weekend and see what happens - it doesn't seem to difficult to do. Thanks again for all the constructive help guys!

 

[The73vetteman]

Brake fluid should be changed every couple of years. It absorbs water, and that leads to corrosion, which leads to problems.

J

 

[GaryS]

In my 35 years of driving experience, a pedal that goes to the floor without any underlying visual issues, leakage, etc, then it is often the master cylinder. Can you pump your brake pedal and get a semi-firm pedal with some stopping power? If so, then I would bet you your favorite beverage that this is your problem.

Of course, I would do a visual inspection and look for a leaking caliper or a dragging brake. You can check for dragging brake by rotating the tires and then make sure that they all rotate freely. Then step on the brakes. Release the brake pedal and make sure that all tires still rotate freely.

Gary

 

[django10000]

It ended up being that the brakes needed to be bled after all. After I did that, the pedal was firm again. There seemed to be a lot of air in the lines and I can only suspect that the place I bought the car from a few months ago didn't change the fluid or did a lousy job of it. Anyway, it ended up being the cheap fix this time...hopefully it stays that way. Thanks again for all the help!

 

[minifridge1138]

I'm glad that was the problem.
Since you said someone had been working on the brakes, i thought human error was the most likely cause.
Pay attention to your brakes. If they get soft again, then you actually DO have a leak and you need to find/fix it.

Good Luck and enjoy the drive!