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Air Bubble Or Master Cylinder


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i have 15k miles on my brakes, drums, and resurfaced rotars front and back. I noticed they were working different but thought it was just the change of everything being new. Before they were changed the car stopped on a dime, i barely had to touch the petal and it was high. My home mechanic who i trust said they were all but shot and that i should have been hearing squealing and that someone put the wrong pads on it causing sand to get in the drums. When i got it back i had to re-learn the breaks. The pedal was midway and much harder but i also noticed when rolling to a stop that at the distance at which the car should have stopped it felt like it would slip roll couple more feet and come an almost abrupt stop. a very slight lunge maybe the word. it is still doing the same thing only the pedal is lower and getting squishy... is this just normal wear for the breaks? It has become more noticable the last two weeks. im jerking myself around cause i cant ever judge the breaks right now that it has changed agian. i hate that I havent been able to stop smooth like i use to before. they stop great at high speeds and quick and are functioning right otherwise, its just rolling then stopping. the fluid is just under max.

i have tried to adjust the brakes by putting it in reverse and hitting the brakes and gas at the same time. and it does nothing. i could always tell the difference in my crappy grand prix. if i repeatedly bottom the brake pedal it gets harder and higher but goes back as soon as you take your foot off the brake. oh crap i hope its not the master cyclindar... could the moron doing the brakes wrong origianlly have screwed up the master cylinder? if ti is the cylinder i may have an upcoming out of state trip FL to AL or GA can I wait til I come back? if its the cylinder or something other than a bubble it going to my mechanic i never trust shops

i do not know anything about breaks so is there an easy way to bleed the bubble with out digging under the car. I need to have my oil change and would like to know what symptoms could be cause i know when i take my car to a shop they will try to rip me off as normal. they should just bleed the breaks and refil. how much should this run if that is what it is?

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First, to check the power brake booster. Start the car and let it run for a couple minutes. Then turn off the engine and then depress the brakes. Make note on the feel and how far down the pedal goes. Release the brake pedal, and then depress it again, note where it stops the second time. Release and then repeat again. Does the pedal stop at a higher position each time? Next Depress the pedal and then start the car. Does the pedal go down further? These tests will tell you if the brake booster is working and / or leaking.

These cars have 4 wheel disc brakes, so putting it into reverse to adj the drum brakes is not valid. Note there are a small set of drum brakes located inside the rear rotors, but this is for the emergency brake, and I do not believe that this has a self adjuster on it.

As far as the brake pedal feel changing radically after your home mechanic worked on it is a little distrubing. There are too many possibilites to diagnose this over the internet. BUT I would strongly recommend taking you car to have the brakes looked at. I believe that your mechainc made a mistake, for safety sake get it checked out.

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respect my authorit-iiiii! my mechanic has skillz. he has 30y+ experience working for the county on all vehicles including volvo work trucks with air brakes. he owns a toyota and a honda. im only questioning so i know what to ask him and tell him when i call. not that i doubt him im just efficient!

brake pedal got harder and higher with each pump. more of a distance from 1st to 2nd pump. shorter distance and much harder on 3rd. it got brick hard when i pushed it the 4 time to start it. brake pedal dropped alot when i started the car.. so now what?

another thing i noticed since the new brakes.. when im stopped at lights i loosen up on the pedal as normal and if i dont keep firm pressure i start rolling. the old breaks were more lax. it happens more frequent than me just not paying attention. or at least i dont think i should be moving which is why i always thought it was a "enguage" point for the new brakes. he used all toyota parts too. so i didnt know if maybe it was a diff grade that might causing issues. same manufacturer same part

im super sensative to my car. I can tell the slight difference in idle from premium gas from mobil vs sonoco, shell, chevron, etc. and from an oil change using synthetic mobil one w lucas stabilizer vs no stabilizer. so im not sure if im over reacting on what is normal? the pedals not horrible squishy im just noticing a change that has caught my attention... im what you might say an*l

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Well the tests you just ran indicates that the power brake booster is working and does not have a vac leak. Some metallic brake pads need to be warm before they have optimal brake performance. It is possible that he installed a set of metallics and you are noticing the difference. Does it feel different after you have done several stops to warm up the pads? It may just be that you were used to organic pads, and you now have metallics. Does it stop straight, without pulling to either side?

Have you mechanic drive the car, and ask if metallic pads were installed. It sounds like you trust your mechanic so if there is a problem he would let you know. Without a test drive I cannot make any further suggestions.

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Well the tests you just ran indicates that the power brake booster is working and does not have a vac leak. Some metallic brake pads need to be warm before they have optimal brake performance. It is possible that he installed a set of metallics and you are noticing the difference. Does it feel different after you have done several stops to warm up the pads? It may just be that you were used to organic pads, and you now have metallics. Does it stop straight, without pulling to either side?

Have you mechanic drive the car, and ask if metallic pads were installed. It sounds like you trust your mechanic so if there is a problem he would let you know. Without a test drive I cannot make any further suggestions.

Im goe'n with air in the line. Don't think they put organic on the Lex. He may have put ceramic. But the low pedel and weird pressure...air I think. Let us know.

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i think ceramic cause when they went bad the first time there were no squealing or symptoms at all. i had no idea they were almost shot. he would have only replace w the same or better. he use to ask what i wanted when i was younger and broke.

i put the car in reverse w the emergency brake on and no brake pedal and gased it you could feel it hunker down and enguage. lol i did this twice and so far i havent noticed the rolling and seems to almost be stoping smoother. not sure if if just been over compensating to correct the problem but we will see how it goes. pedal is still in the middle and firmer like when i got it back w the new brakes. i go for oil change tomorrow and will ask bout the bubble.

are metallic the kind that will "slip" when cold. cause im not sure i can pin it to being cold. i havent noticed that yet. will ceramics slip?

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i know the ebrake doesnt function w regular brakes but i tried it to see if it changed the pressure or or move the bubble in the air line for different effects.

it was air in the brakes system by the valves but not bubbles. took it to my mechanic after i called him and explained. His first guess was the master cylindar. the cylindar had no leak or seeping fluid. he found when he uncapped the line on two of the wheels that air came out before liquid so there was air in the system but not the same effects as bubbles in the line which made it seem like the cylindar.

my pedal is higher and softer it is the normal differences for new brakes now. yippee! thanks dudes. it should be solved now tossed him a $20 and was on my way. if you are having to replace a cylindar the toyota brand is around $500 for the part but I was told you can get quality aftermarket for a couple hundred and not to use a re--??? pair remodeled.. damn it reconditioned? one.

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respect my authorit-iiiii! my mechanic has skillz. he has 30y+ experience working for the county on all vehicles including volvo work trucks with air brakes. he owns a toyota and a honda. im only questioning so i know what to ask him and tell him when i call. not that i doubt him im just efficient!

I', sorry, but I have to question the abilities of a mechanic that does major brake work, and obviously opened a brake line or two, and does not bleed the brakes after he is done? There is no excuse as to why he would not notice the problem when he test drove the car, and if he did not test drive the car it is even worse.

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i dont know enough to argue that.

if it wasnt your car you wouldnt notice the symptoms esp on a test drive. being familiar w the car you notice it alot cause it just wasnt the same. i knew by compairison not the presence of symptoms. the symptoms grew by addition so in the beginng it just was the pedal diff which is normal position and pressure on other cars. if i let someone borrow my car for a week or sold it before i took it to the mechanic they would never know or notice it cause it drives like other cars.

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