Brake pedal touching floor- mechanic can't help

Hi everyone. Although I probably should, I don’t know a thing about cars beyond how to get them to the mechanic and back. So I’m at a complete loss, but I’ll try to keep it short.

I had the brake pads, rotors and calipers replaced about 2 weeks ago on my Town and Country because they sounded really bad when I’d come up a stop (grinding sound) and everything was going fine after the replacement until a couple days ago. I went to press the brake pedal and the entire thing hit the the floor before it would actually stop the car. Took it to the mechanic and he said I had 2 leaking calipers, so he replaced them. I pick up the car, drive it for about half an hour and everything is fine until bam, all of a sudden I’m having to press the brakes to the floor again. So I take it back. He says now only my left caliper is leaking, and replaces it, replaces my brake fluid, bleeds the brakes, and I drive it for about 15 minutes before bam, I have to press the brakes to the floor again.

So I pull over and look under the hood and there’s antifreeze just pouring out making a huge puddle on the ground. But there was no indication while I was driving that the engine was getting hot. In fact it was maybe 65 out and I never even broke 35 mph. So I get back in to take it back to the mechanic and the brakes go from working okay, to having to hit the floor, to being okay, etc on and on.

The mechanic checked the booster, the master cylinder and looked for any leaks where I could be losing brake fluid and now he says he’s really busy today and can’t look at it further until tomorrow. Meanwhile I’ve been missing work this entire week and I need to know what’s going on.

Can any of you wonderful people please give me some insight into what could be causing this problem? I’m at a loss and don’t know what to do. Any input is very much appreciated.

Not sure if it’s relavant but the car has 60K miles, ones previous owner and I haven’t had any other problems with it. Recently did use it to trail a u haul while moving 900 miles away, but there were no issues.

Ali

Whenever you go on line to get advice about your vehicle, you should always include the year of the vehicle.

It would be the same as walking into a parts store, and asking for a part for your vehicle without telling the counter person the year of your vehicle.

The counter person needs to know the year of the vehicle before they can start typing on the computer.

Tester

My advice is find another mechanic. Also you seem to have two problems, brakes and coolant.

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+1
And, I can’t emphasize strongly enough that the OP needs to have her vehicle TOWED to a new mechanic’s shop. In the event of an accident, the potential liability of driving a car with a known major brake defect would be…enormous. In fact, your insurance company might refuse to cover damages from an accident involving a vehicle with a known brake defect.
:worried:

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Have seen this problem occur a lot with ABS systems where the mechanic doesn’t open the bleeder to compress the caliper piston and pushes old contaminated brake fluid back into the ABS module. You end up with a piece of debris in the ABS module causing an accumulator to not hold brake fluid pressure. Most likely it’s going to take an ABS module to fix this problem and I seriously doubt you’re gonna get your mechanic to accept responsibility as it’s impossible to prove.

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My guess without seeing car is the master cylinder is bypassing internally. Your mechanic probably blew it out compressing original calipers back in place. And yes he soaked up a bunch of cash from you then he has no time to make it right. You’ll need to get a better mechanic.

I apologize for any confusion, it’s a 2008. Right now the mechanic is saying he’ll get to it tomorrow which is frustrating because I can’t keep missing work and public transit/Uber isn’t an option (about an hour’s drive all back roads). He’s saying to leave it with him until tomorrow evening. Do you think it would be a better idea to just take it to the Chrysler dealership and have them do something?

I can understand a one day delay in getting to your car. It’s not that he was expecting you back.

Problem I can see is that if you take it to a different mechanic you will certainly have to pay for any repair they make. Taking it the “old” mechanic, he might fix what’s broke at a reduced cost because, in my opinion, he was certainly wrong in his previous diagnosis and charged you for fixes that may not have been needed, but you will have a heck of a time proving it.

Goes to show the importance of finding a trustworthy and qualified mechanic. You might want to have a “serious” talk with the guy when you drop off your car and if you feel uncomfortable take it to another place. Heck, the guy literally put you in danger with failing brakes.

That’s true. But if you don’t you may end up paying for the bridge abutment you hit.
I strongly urge you to get towed to another mechanic. ASAP. Your master cylinder may be failing (my guess), or Pete may be right about the ABS module, and you need to get this repaired. This is a “must do at all cost” repair.

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He said he checked the master cylinder, is there something he could have missed?

I tend to disagree with you

In my opinion, it sounds more like a bad brake master, versus a bad abs hydraulic component

And by the way, I don’t think the brake master is bad, because of anything the mechanic did

I suspect it was bad all along, and the mechanic just doesn’t know how to properly diagnose brake problems

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My first SWAG is also the master cylinder and I would also strongly suggest getting the car to another shop. While it is possible that the shop is honest and knowledgeable it seems very unlikely based on the OP’s posts.

Here’s my guess. Just a guess mind you. This all happened when the brakes were bled, after changing the pads during the first repair. For the past 9 years, the whole life of the car, the hydraulic fluid pistons in the MC and calipers were sitting basically in one narrow range inside their respective cylinders, moving very little even when applying the brakes. Meanwhile over the years there was some water intrusion into the fluid & a little corrosion (rust) started to occur at places on the cylinder walls where the pistons were not wiping clean by using the brakes. So far, so good, you don’t need those sections for the brakes to work. Here’s the problem: During the brake bleeding operation those pistons got pushed into the corroded part of the cylinder walls, and movement that tore the internal seals. There’s probably more torn seals that haven’t been replaced yet, among the wheel calipers, the master cylinder, and possibly the brake booster.

OP’s shop is going to have to figure out which of those parts have not been replaced, and replace them. It’s not entirely a guessing game. The shop can clamp off various sections of the brake system, and if the pedal returns to normal then, they’ll know the problem is in the part they clamped off. But with this problem at this stage, I’d be inclined to go ahead and replace all the calipers, and the master cylinders, and before that give the entire system a thorough bleeding and replacement with new fluid of the proper spec for the car. It’s possible the brake booster could be bad too, and if so that will be clear b/c the pedal will still not be firm, but that part can be replaced independent of the other stuff.

The comment above by pete p should be considered too. Especially if the shop tech didn’t follow the proper procedure as described to minimize contaminating the ABS system during the bleeding procedure. On some cars the ABS can only be bled properly by using a car specific scan tool.

OP … to minimize this problem happening in the future, good idea to replace the brake fluid every couple of years. Make sure the shop uses a pressure bleeder.

Unlikely the cooling system problem is related, but that sounds like a deferred maintenance problem too.

Offhand, I would suspect the master cylinder and also wonder how he “checked” it.

The part about having 2 calipers leaking (on a 60k miles vehicle) also sounds odd as does the repeat caliper leak. Especially considering a brake job was done a few weeks previously and a leaky caliper should have been noticeable then.
How often do calipers leak? Very seldom and supposedly multiple calipers were leaking.
And then a return trip for another leaking caliper? What are the odds…

As for the coolant leak, maybe overheating somewhat due to the brakes dragging?

I tend to agree with you that maybe taking it to the Chrysler dealership for a look may be a good idea.

You can do a MC test yourself. Turn the car on. Do not move it because you know the brakes are dangerous. Press on the pedal. Sinks to the floor? OK. Now stomp on it very hard and fast. Does it still sink to the floor? No? Then it’s the master cylinder.

Someone with a great deal of experience can test a Master cylinder like that @shadowfax but a beginner DIYer might be clueless as to how to feel for the downward creep when slight pressure is held on the pedal. Like tightening spark plugs properly you must develop a talent.

I don’t think it takes much feel to tell the difference between “this feels really mushy and sinks to the floor” and “this feels rock solid like it should.” I’m not talking about the light pressure test, I’m talking about stomping the daylights out of that pedal to move the piston faster than the fluid can leak past its seal.

You can disagree all you like. I know what I have experienced myself in this shop that I have worked in the last twenty years. I can’t count how many ABS modules we’ve had to replace due to arrogant, misinformed, or plain lazy techs. If you compress a caliper piston on and older car with ABS and don’t open the bleeder, then old nasty contaminated fluid is pushed back into the ABS module, possibly compromising accumulator integrity. If it was a bad master it would be repeatable, not intermittent.

What if OP’s shop temporarily disabled the ABS by pulling its fuse, then tested the brake pedal to see if it was still misbehaving? Would that be diagnostic in the situation where the ABS fluid has been contaminated by an improper bleeding method?

Thank you all so much for taking the time to reply, your responses are really eye opening and made me feel way less out of control. So, mechanic replaced the master cylinder and everything feels okay far. And, he only charged for the part, no labor, so I’m happy with that although all that missed time at work is painful :confused: thanks again everyone

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