M friend with his 98 gmc. When stopping the breaks are normal until getting slow then the abs motor comes on and the break pedal sinks to the floor. The truck stops but the abs motor runs constant until you release the pedal. This is happening on dry roads. What is there to check before condemning the abs module?
View 4 RepliesA friend brought me a car with the issue that the brake pedal sinks to the floor when braking. She said it was never low on fluid so I replaced the master cylinder and bled all of the lines with a friend pumping the pedal. The pedal would still sink to the floor. I tried vacuum bleeding the brakes and found that the front left consistently had large bubbles.
I Teflon taped the fitting on the calliper and the bleed screw which improved the problem but didn't fix it. I then replaced the calliper. The front left calliper still won't bleed and the brake pedal still goes to the floor. When I bleed it the regular way, the fluid comes out of the bleeder like it bled nicely. Neither of the rubber hoses that connect to the calliper have any visible damage. I had a friend pump the brakes while looking at the hoses and their is no bulge or swelling in them. Could the ABS need to be bled?
My B6 purchased exactly three weeks ago has had a soft brake pedal since day one. By "soft," I mean that when parked with the engine running and applying moderate pedal pressure, the brake pedal provides some resistance but sinks to the floor. If I pump it up a few times, it temporarily gets much firmer, but eventually sinks to the floor again after a few seconds. Now the car so far has never failed to actually stop, and it can get into the ABS. But during an abrupt (okay...panic) stop last week, it did go to the floor while the car was still moving. That's when I decided that was enough and took it back to be serviced.
My expectation was that there was just a small amount of air in a line somewhere, and that they could bleed the system and fix it. That was my experience with my B5: it was very sensitive to the least little bit of air, and if it wasn't thoroughly bled after brake service the pedal often got mushy and could find the floor. But bleeding them always get the pedal back to normal. So the service advisor said that he "had the service manager drive [my car] and compare it to a new Passat [on the lot] and talked to "Quality Tech. Manager to confirm." And the confirmation was that my brake system is "working as designed." In short, they say the brakes are working properly and there is nothing to fix. So I have now picked up the car and it still does the same thing.
Now I can (and will) bleed the brakes on my own over the weekend. But I would like feedback from others as to whether or not their brake pedals regularly see the floor. I just can't see this being the way any hydraulic brake system should work..
I have a problem about which the mechanics I have asked are baffled: In cool, cloudy or sunny weather, my brakes and break-pedal pressure are fine (the mechanics have said I have good fluid, brakes, etc.--they can find nothing wrong--and, of course, it never has a problem when they test-drive my car). However, when the weather warms up and it's a bright, sunny day, my brake pedal loses pressure and slowly sinks to the floor--a dangerous thing at intersections. There's slight pressure if I pump the pedal constantly while at a light; but, without pumping, the pedal immediately sinks to the floor.
This is a real problem, because this problem always occurs right when mechanics are not near or not open for business--and none I've talked to have ever heard of such a problem. The bright, hot sun's affect seems to be key, because if it's 80 degrees outside and cloudy, I don't have the issue--but, then again, I don't usually run the air conditioner if it's cloudy. As such, I'm not positive; but, this may be tied to when I turn on the air conditioner--as though the two share the same vacuum system.
yesterday i gave the 02 diesel a treat, 3 new calipers 4 new rotors, and semimetalic pads. the reason for only 3 calipers is the driver side was just replaced 2 months ago after it locked the wheel up on me. both rears were seized so i only had front brakes, and the passenger side front was leaking.
anyway, all new parts and the pedal is fantastic, besides the truck stopping again. this afternoon on the way home from the shop i stopped at a red light. breaks are rock solid. then all of a sudden, the pedal slowly sinks to the floor. but the brakes still hold. i get home and test them. again, pedal slowly sinks to the floor, but they hold. i am thinking still some air in the system, and park hte truck, with the intention of bleeding them again tomorrow.
i get out and see fluid all over the driveway. great. something in the front of the axle is leaking. the frame is drenched. whatever it is, is in front of the frame, on the engine side. what is in there, the ABS unit?
My Sienna 2005 experience intermittent complete brake failure 3 times within 18,000 miles,the brake pedal goes to the floor and it does not slow down, so I coast until I stop. However, when I release the brake pedal and then reapply the brakes, it works fine. A non-Toyota mechanic thinks it's due to malfunction of ABS. The dealership is unable to finds error codes and brakes work fine when the Sienna is in their hands. I scared that the brakes will not work the next time I reapply the brakes.
View 30 RepliesWe have a 2005 Toyota Camry, had it since 30K miles/2008, now has 94K miles. Since we have owned it, the brake pedal feel has not been great, kind of mushy. It is the way this generation Camry's are. It gets driven mostly on fwy, so not much brake use. At 92K miles I changed the front pads and rotors, pads still had 30% left on them. The rotors were somewhat warped. Brake fluid has been gravity flushed every 2 years since 2008, last one in 2012.
Now, the problem is when wife drives it, twice at a lengthy red light, she has noted that the brake pedal "almost" sinks. It did not go to the floor, but the level went lower. The car did not move during this events. With the newer ABS brake systems, on all my three cars, after a full stop, I can push the pedal down further, almost close to the floor. The Camry is the same way, just with a baseline of mushy pedals. My wife only drives one of the other ones (Dodge Caravan,)and has not complained about that one.
The brake fluid level is solid/steady, no leaks at the wheels either.
Now looking at whats involved, seems I can change the master cylinder myself. The question is do I need to? I don't mind paying a mechanic to do a diagnostic too, just not sure what they are going to do. I believe, just as a defensive measure, they will go ahead and change the MC (which then I might as well do it myself). I could also continue to drive it, but don't want to be stupid here.
I have an '89 GMC Sierra which has the standard rear wheel anti-lock brakes offered that year and a vacuum booster. It has about 180,000 mi. on it. I have a problem with the brake pedal fading to where it goes completely to the floor. This happens whether the engine is running or not. The brake warning light is not on (but is operable), there is no air in the lines, and their are no external leaks. The resevoir has stayed at full level. I rebuilt the master cylinder and the bore looked great as did the seals, but I installed the rebuild kit anyway.
There has been no change in performance. Can this be a problem with the isolation/dump valve assembly leaking internally. I would think that would cause the warning light to come on. The i/d valve is a costly part to replace and I hate to experiment on such a solution without some confidence in the source of the problem. The GM Service Manual troublshooting indicates air or internal master cylinder leakage is the culprit, and indicates the light would come on for any i/d valve problems.
I was driving around today and had to hit the brakes really hard for the first time. ABS kicked in and during the ABS 'action' the brake pedal rapidly went to the floor. With each 'pump' the ABS made it felt like the pedal sunk slightly.
This was on dry pavement, a little gravelly / dirty and the car stopped rapidly, but just as I stopped the pedal was VERY close to the floor, and with just a touch more pressure it did in fact hit bottom.
Sounds to me like the ABS pump needs to be bled, is that right? Can I do that myself with a VAGCOM? I hate having the dealer do anything, even if it is their job. How to SAFELY confirm if cars does / does not do this as well?
2005 Volvo S60 T5, 90,000 miles. The brake pedal depresses almost to the floor. Dealer service has not had a solution to this problem. All brake components are supposedly nominal. Might pedal position sensor be faulty?
View 1 RepliesMy 04 Camry is having brake issues. It has 205k miles. The front pads are great and the back shoes are great. (Drums in back) I've had them adjusted multiple times but my pedal still goes almost to the floor. It's not the master cylinder cause I've already replaced that. The pedal doesn't bleed off either. But I have bled the brake lines and there is no air left in the lines.
View 14 RepliesMy mother went out 2 days ago to go run errands, she stepped on the brake pedal and it went to the floor (car still in garage and in park, low mileage car 81,xxx garage kept). I have not been able to duplicate the issue. The fluid has been changed twice since new, no signs of fluid loss, undercarriage inspection revealed nothing. I am thinking maybe a vacuum hose issue.
View 2 RepliesWhen I go to start and depress the brake pedal it goes all the way to the floor. The brake fluid is at the full mark and my 2011 has only 25k miles. Where should I look since it did not go all the way to the floor when I forst got it with 6K miles.
View 19 RepliesI drive a 1991 F-150 Lariat Extended Cab. Out of the blue, my brakes decided they didn't want to work unless the pedal is about 1/2 - 3/4 of the way down to the floor. As soon as I release past that 1/2 mark, they shut off. While this makes it great for tailgaters, it does not make it great for police officers.
We have already replaced the switch thinking maybe it was that, but alas it was not. I was reading in a couple difference places about the multiswitch? However, the symptoms other people had were similar, but not the same. I never tilt my steering wheel, so I dont know if that's the issue!
2013 Prius c Two, bought brand new with 15 miles on it 5 weeks ago. A few times when driving, I noticed the brakes seemed weak, like they weren't stopping the car very well even at low speeds (My driving is mostly in town on residential streets, so I'm rarely going over 35 MPH. Even so, I'd have to really mash the pedal all the way to the floor to get the car to come to a complete stop, otherwise it would keep moving forward. Several times I ended up about 5-10 feet past the line, sticking the front bumper into cross traffic. Luckily no one hit me. I chalked it up to the quirks of a different car than the one I was used to, and figured if it kept happening I'd take it to the dealership.
On Monday, my wife was stopped at a red light. The light turned green and the car in front of her started to move forward. After a few hundred feet, he suddenly slammed on his brakes. She said her brake pedal went all the way to the floor, and the Prius didn't slow down at all. She hit him going about 25-30 MPH and totaled the Prius. She's an excellent driver and I've been with her before when she's had to panic-stop. She's never driven a car without ABS, so she is used to pushing the pedal hard and keeping her foot on it. She wouldn't even know how to "pump" the pedal. She swears the pedal just went all the way to the floor and the car didn't slow down at all.
For the past several weeks, my daughter reports that she has to put her foot almost all the way to the floor to get the brakes to work. The brakes do not have an effect until her foot is 1-2 inches from the floor. It usually happens after she has been driving for a while without pressing the brakes. I’ve driven the car numerous times but haven’t been able to replicate the problem. Her commute is approximately 10 miles each way in stop and go traffic. The car is a Volvo xc70 with 200k+ miles. I've had it looked at by a mechanic who didn't find anything but it's continuing to happen. I'm suspicious that it may be a master cylinder problem and concerned about complete brake failure -- should I be?
View 7 RepliesWhen I press the brake pedal, the car will stop. But if I keep pressing it while the car is stopped, the pedal wants to keep going towards the floor. I have to press hard for it to do this. I have bled the brakes. I've checked the calipers and the hoses for leaks and don't see anything. The master cylinder is topped up and I don't see any fluid underneath it. It doesn't appear to be leaking. The funny thing is, when I turn the engine off and press the pedal, the pedal comes to a stop and doesn't want to move after I pressed on it as hard as I can.
View 2 RepliesI have a 2007 Sonata GLS 4cyl. Anyhow lately my brake pedal is going right to the floor. The brakes seem to work fine, but if I keep constant pressure on the pedal it will slowly go all the way to the floor. My rear rotors and pads have been changed a couple of months ago and I'm pretty sure my front brakes are good. What could be causing this? I also checked underneath the car for leaks and there doesn't seem to be anything leaking underneath.
View 6 RepliesI have been working on my 01 Elantra for 2 days now. My problem is that I have absolutely no brake pedal at all, it just goes right to the floor. and this is only when the car is running, when it is off I give it a quick pump and i have a nice firm pedal. I installed a new master cylinder, bench bled it and all that jazz. I replaced the rear brakes and a wheel cylinder, I have also bled the brakes multiple times, and mutliple ways. bled the master while on the car and all the brakes while the car is off and while it is running. I dont know what else could be wrong with this. I looked at all the lines and there are no wet spots, no hoses are swelling up. everything looks top notch...i just have no brakes why.
View 15 RepliesI have a 99 Blazer 4x4 with ABS. Brake pedal just went to the floor and car stopped eventually ... a bit scary. I've checked all the brake lines and the inside of all wheels and there is no sign of fluid anywhere. All pistons seem to be where they need to be with backing plates nicely visible.
I pumped the brakes quite a few times and same result ... but I'm not pumping fluid on the ground. As expected I've also checked the reservoir and its full. Didn't see any leaks so its full. I'm guessing that the master cylinder has given up the ghost ... truck has 470,000km so things wear out.
I have a 96 voyager, it has been a great car for the last 10 years I've had it. My brake pedal goes down to the floor, it gives brake but I think barely and my brake light comes on. I have Bled it twice and changed the master cylinder , neither worked, I'm perplexed, my mechanic thinks it is the abs.
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