Yaris Soft Brake Pedal Problem

[xdarkxfirex]

Bought this 08 yaris base last may. Brakes always felt soft. No leaks, had bled several times. I decided to buy a quality dorman master cylinder, not much difference.

If I adjust the rear brakes, the front doesnt work as well and pedal feel doesnt change much. This is frustrating. I've tried everything, tested the booster many times and still nothing

[CTScott]

You might want to change the flexible portion of the brake hoses that connects between the rigid line and the front and rear brakes. Some people upgrade them to the braided stainless aftermarket ones, but just putting a fresh set of OEM ones on there can make a world of difference.

[Jcp123]

Might be worth it to bleed the brakes, but with a new master cyl, I'm guessing you did that already?

[cali yaris]

stainless brake lines will firm up the pedal some.

[CoryM]

Try this:

With engine off, pump the pedal several times (approx 1 pump per sec). It should get harder as the brake-assist depletes. On the last pump, hold it and feel how high the pedal is. Release the pedal for 10seconds and apply it again with the same amount of force. Is the pedal at the same height or not?

If the pedal gets higher/firmer as you pump it means you either have:
-air in system
-poorly adjusted rear brakes
-front calipers which are retracting the pistons too far (less likely).

There are a few other possible, but unlikely causes as well.

If the pedal is always in the same spot, it may just be how the car is. Are you comparing it to another Yaris? Every car has a different pedal feel.

Cheers.

[xdarkxfirex]

The booster builds up pressure, and I've tested it and it's fine. The lines were bled and I made sure they were bench bled properly when I installed the new master cylinder.

No leaks as well. As far as adjusting the rear brakes, doesnt make much of a difference, and pads still have plenty of life.

[WeeYari]

Might be worth it to bleed the brakes, but with a new master cyl, I'm guessing you did that already?

^ in the original post had bled several times.

Are you comparing it to another Yaris? Every car has a different pedal feel.

^ this.

[xdarkxfirex]

I realize that cars have different pedal feels, but this goes to the end

[sheekeebut]

Down to the floor?

My experience: they're economy-car firm. As in, there's some softness in there to keep grandma from bashing her head into the wheel in case of panic stop. Mine are bone stock like yours. Bled a couple times already. I'm almost certain the softness is the remaining flex from the reinforced rubber lines, but I can't confirm this without switching out the lines to steel braided, which I'm not ready to do yet. As long as you're not hitting the floor when full pressure is applied, I think you've got the standard (albeit soft) brake feel.

I had the same concern. Then I tested it against my colleague's Hyundai Accent (comparable), and they were pretty much the same.

[ezhacker1]

Switching to braided is awesome for the first month, then you get used to the firmness difference. Pedal is much more sensitive as expected.

[nortonfb]

I'm using ceramic brake pads and they have a firmer feel.
Also, as someone stated that the rear brake adjustment does
make a big difference in feel.
Norton

[xdarkxfirex]

I guess it's true, I'm just not used to having such a soft pedal. We bought this car last may, had 122k on it off lease, was around 6700 with tax, licensing, extended warranty etc.

Pretty good car all around, I didnt even look at the options much, but regretted buying a car with no power locks or ac. Gets really good fuel economy though.

A few months back, I had tried to bleed the system, and the wheel cylinder was stripped and kept leaking so I was in a panic and took it to the dealer of all places, which charged like $286 for an aftermarket wheel cylinder, with no brake flush, or service. I felt stupid afterwards considering these are fairly cheap parts. The abs light came on, but was fixed because the spiral cable was damaged and recalled. I also got to worry about when to put in my new water pump since the bearing on this is gone, and its pretty bad working outside in the cold.

I take good care of my cars, and like to fix any issues asap. New iridium spark plugs cost about $38 for 4 at canadian tire when on sale, and I bought a bunch of valvoline oil for $2 a quart. A dozen filters too for like $3 each. Nothing beats learning to do things yourself over getting ripped off at a shop.

[Exiwolfman]

Soft pedal on Yaris could be do to rear brakes out of adj and also slider pins and brake shoes seized in the calipers ...that is the two first areas to have a look ....brake bleed last and unless u have lots of air in the system it will not resolve soft pedal till u resolve the points mentioned.
As for water pump that one can do in a driveway not a hard job ur looking at about 100$ in parts plus coolant its about 30 min job ...plus time to get air out of the system.

[invader166]

I finally managed to get my brake pedal to feel a bit more "normal".
It's incredible how much of a difference rear brake allignment makes. After upgrading to ferro-carbon pads, changing to higher rated rotors and installing a set of braded stainless steel brake lines, the was some slight improvement, but not super amazing. As soon as I adjusted the rear brakes (3 clicks on the hand-brake) the pedal instantly feels harder, and i would even say proper.

Thank you for all the tips everyone!

[tmontague]

Anytime I have the rear wheels off the car (about 4x a year) I always adjust the start adjuster on the rear drums. I tend to slightly over adjust so that the wheel does not freely spin much on its own and the e brake only goes up 2 clicks. Always noticeable an makes a big difference.

I find the self adjuster either never works (they are clean) or the adjustment they do is too slack for my liking. Saves your front pad life a little longer too

[xdarkxfirex]

I thought before it might be a master cylinder problem since I owned the car. Replaced a few of those on this car, and returned the aftermarket ones I got, both centric and dorman. I then used the original New advics brand toyota uses last month. Seemed to be the same. The car does stop and holds pressure but sometimes I feel like I am loosing pressure If I hold the brakes, when stopping. It could also be brake fade. I could press on the brakes and feel like it engages and then doesnt as hard as it did after a second or two. It doesnt inch forward at stops, or sinks when stopping, so I guess it should be fine. Usually a bad master will sink regularly, but I am just paranoid. All my OEM rubber hoses are still fine. No cracks yet.

[IllusionX]

I thought before it might be a master cylinder problem since I owned the car. Replaced a few of those on this car, and returned the aftermarket ones I got, both centric and dorman. I then used the original New advics brand toyota uses last month. Seemed to be the same. The car does stop and holds pressure but sometimes I feel like I am loosing pressure If I hold the brakes, when stopping. It could also be brake fade. I could press on the brakes and feel like it engages and then doesnt as hard as it did after a second or two. It doesnt inch forward at stops, or sinks when stopping, so I guess it should be fine. Usually a bad master will sink regularly, but I am just paranoid. All my OEM rubber hoses are still fine. No cracks yet.Are you sure it's not the AC on it'ls duty cycle? Mine does it holding the brake. Suddenly the pedal feels much lighter.

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[xdarkxfirex]

Mine doesnt have ac, but now that you mentioned it, it might be the vaccum booster because it did have some fluid in it for a while from the aftermarket ones that went bad. I cleaned it out well. Really have no idea. Sometimes with these cars the pedal feels softer than other times. My brothers newer 2015 has a much firmer brake feel than these older ones.

[xdarkxfirex]

I notice its when I come to a steady stop sometimes when i feel it. I could be not being depressed enough to really engage noticeably.

[xdarkxfirex]

Could it also be the rubber hoses? Where is a good place to buy a set of stainless ones?

[Exiwolfman]

Adjust the rear drums and make sure the front slider pins are free , rear makes a huge difference in how the brakes feel on Yaris

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[xdarkxfirex]

It does, but you have to adjust them regularly. I just did the other day. I ordered a set of new front brakes just to see if it will help the problem go away as well. I've pretty much narrowed it down to that now. Dont know if proportioning valves, or a booster can cause the same problem. I've heard mixed things. Sometimes you have to press twice to notice the brakes engage, it doesnt engage, or you press brakes feel warping then it sinks a little.

[IllusionX]

I still don't understand. Are you pressing the brake pedal and it goes to the floor without slowing down at all? Like the first time you press the pedal after pushing the piston in for new pads?

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[Exiwolfman]

It does, but you have to adjust them regularly. I just did the other day. I ordered a set of new front brakes just to see if it will help the problem go away as well. I've pretty much narrowed it down to that now. Dont know if proportioning valves, or a booster can cause the same problem. I've heard mixed things. Sometimes you have to press twice to notice the brakes engage, it doesnt engage, or you press brakes feel warping then it sinks a little.Are your slider pins moving and lubed are the front pistons moving etc ...think you are putting way to much though in to this , adjust rear and make sure all is moving upfront and you don't have a seized calipers .

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[xdarkxfirex]

Yep, the sliders are lubed up pads uniformally wearing. the lower pins sometimes feel like the stick a little more, even though the bushings are fine and they are greased. Its not a sink to the floor issue, its just sometimes you dont feel the brakes engaging at all, but pedal still has pressure.

[Exiwolfman]

Yep, the sliders are lubed up pads uniformally wearing. the lower pins sometimes feel like the stick a little more, even though the bushings are fine and they are greased. Its not a sink to the floor issue, its just sometimes you dont feel the brakes engaging at all, but pedal still has pressure.Did the pistons push in when brakes taken apart ? The uneven brake pad is typical of Yaris the inside pads do wear out sooner .
You may have sticky caliper

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[xdarkxfirex]

Yes, the pistons push back, and they arent seized. Thats why im kinda scratching my head.