Soft brake pedal

[Kris]

Hello
I’m new here but watched a lot of Eric’s videos and loved them!!!
I have a 2008 Toyota Camry 4 cylinder. Some time ago I start to experience low performance from my brakes. I have to press on the brake pedal pretty far to stop the car. So I started to look for the problem. Replaced front rotors and pads, replaced rear calipers , rotor and pads. Bled the whole system starting from the farthest wheel from the master cylinder to the closest (back passenger side,back driver side,front passenger side and front driver side). And I still experience the soft brake pedal. What else might be the problem? I do not hear any whistle noises coming from the power booster and also when the car is off and I pump the pedal is hard as rock. But as soon as I start the car the pedal goes almost all the way to the floor (which I think what it suppose to do). Is it my master cylinder? How can I check that?
Thanks for any help.
Kris

Topic

[David]

It sounds like your Master Brake cylinder is starting/has failed. Also check for any leaks, such as a leaking slave cylinder if you have rear drums. Other possibilities is a swelling hose (maybe but its probably your MBC)

[Lorrin Barth]

The pedal shouldn’t ever go all the way to the floor. You should also be able to apply the brakes two or three times with power assistance due to vacuum stored in the brake booster. Then the pedal will get hard to depress.

[Kris]

The pedal get really hard when the engine is off. But when I start the engine, no matter how many times I press it it won’t get hard

[college man]

see if this helps. The car does stop? I have read that Toyota’s
have soft feeling brakes from design.

http://www.ericthecarguy.com/faq/solving-brake-problems?start=7

[Matthew]

I actually have this same experience. My 2001 Daewoo Lanos has ALWAYS had a soft brake pedal from the getgo. My Master Brake Cylinder went out an was replaced. It STILL has a soft brake pedal even with the new cylinder. Like your’s, My pedal is hard as a rock with no power however the SECOND the car is started if i have my foor on the brake it sinks straight to the floor. How is your stopping ability while driving?

EDIT: Is there such a thing as a “Slave” Brake Cylinder?

[Ingvar]

[quote=”DiarySmgTin” post=120026]

EDIT: Is there such a thing as a “Slave” Brake Cylinder?[/quote]

Actually, it’s slave clutch cylinder. Manual transmission. There are clutch master and clutch slave cylinders. Not on automatic.

OP, though it is most suspicious to blame it on failing master cylinder seals, it may be just a factory design thing. GM, eg, has some vehicles with very soft brake pedal yet they function very well.

So let me ask you this. Was it ALWAYS like this, or it just started? Btw, do yourself a favor and do not toss parts at the car without 1st pointing the problem cause.

[David]

Oh whoops, see what happens when you stop working with cars on a regular basis? Yeah, I meant Wheel Cylinder, Its what accuates the drum brakes. Only applys if you have rear drums instead of rear disc.

And yes, as mentioned, don’t throw parts at the car until you know what the problem is. I learned that lesson last year when my AC clutch froze up and I replaced the battery (dropped to 8v on crank attempt), replaced the starter after the batter didnt fix it. New starter started it twice, and then it quit. Finally talked to an actual tech and we were able to get ideas, like remove drive belt, see if it cranks.

[Matthew]

I almost did the same thing myself (Throwing parts at it). My Car started to Overheat and I was thinking it was something with the Expansion Tank cap. Realized that it was indeed the Thermostat (AGAIN). Some shops offer a Free Brake Inspection. You could call around local shops in you area and find if you have one that will and just drop the car off. If something is wrong they will tell you. With Personal Experience with my Daewoo I realized that As long as the car stops you should be fine. I actually thought I had a bad brake caliper after all the shady work the shop did with the brake work. That problem seems to have gone away.

[Kris]

Sorry for the late reply. Went on family vacation.
Anyway. Brakes seems better now. Maybe they just need to be brake in or something. You guys said to not throw parts at it. But my rotors were bad and the calipers have torn booths. I have to replace those. Also is there a break fluid leak UV die or something?

[George Hebert]

Brake pedal goes to floor when engine is turned on, waiting for Red light to turn green pedal will go to floor if pushed sufficiently, pedal is generally soft, spongy. Brakes stops car. ABS works fine, no indicating light on dash. New Rotors, Pads, Brake fluid, Master cylinder, Booster check valve replaced.
No leaks. ABS Modulator shows no leaks.

Maybe the ABS Modulator electronic control bad?????

I am at wits end, haven’t taken it to the Dealer.

Any suggestions?

[Caleb Stovall]

Have the entire system bled including the ABS system.

[Andrew Phillips]

Providing year/make/model really helps a lot, by the way. The cause of a soft brake pedal is usually air ingress (air in the lines, or trapped in a caliper or wheel cylinder). There are many other causes too, such as fluid leak or low fluid level, swelling rubber brake lines, failing master cylinder, faulty parking brake self-adjusters, etc. If your vehicle is equipped with ABS, there could be air trapped in there also. Some ABS-equipped vehicles require specific procedures for bleeding (i.e. a certain wheel bleeding sequence, having the ABS solenoids commanded open by a scanner during bleeding, etc).

[Author]

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