Car seems sluggish and brakes mushy

[Andrew McMillan]

Hey everyone, new to the forum, so hopefully this hasn’t been covered somewhere else and I’m gonna get flamed…. here goes:

I watched Eric’s video about replacing pads and rotors and took a stab at rep[lacing them myself on my 2006 hyundai sonata, it’s got 128K miles on it. The old pads and rotors looked like hell so adios they went. I purchased some duralast top of the line pads from autozone and new rotors as well. I pulled all the old hardware off and followed the instructions on replacing pads and rotors and had a proper piston compression tool to turn the pistons back in. Seemed super easy enough and went well at first.

After some driving however it seems as though they’re getting mushy and the car seems less… peppy, you gotta get on the gas a little more and it’s shifting differently. after 128k miles I know how it used to feel. I checked the brake fluid thinking that maybe I pushed some gunky stuff back into the system, and it was greenish, like extra virgin olive oil. I’m pretty sure I’m gonna have to replace that as it’s been a while since the system was flushed for sure. Could this be contributing to brake malfunction where it isn’t letting off or something?

Thanks for any helpful tips, and I will update the forum if the system flush takes care of it.

As a side note, I noticed some small grooves on the rotor almost immediately on one of the new ones, and pulled it off to see that there were two small bits of metal seemingly embedded in the pad, i popped those out with a small electronics screw driver, and it’s not gotten any worse. Wondering if these pads are any good. They were the top of the line DuraLast ones…

Thanks again!

Topic

[dave]

after a day or two you’ll get good braking… you have brand new pads on brand new rotors so they are gonna feel slick for awhile.

I also used to own a 06′ Hyundai Sonata. It was dark blue and it ran like a charm. Good car.

[college man]

When you install new pads and rotors.You should do a bedding
in process. also when you reset the caliper pistons.Did you open
the bleeder when compressing the piston? Did you bleed after the job.

[clay rutledge]

On most brakes i do ( my boss dont like it much says it takes too much time) but i open the bleeders to compress pistons and always bleed the entire system.. im sure its not needed but i do it for a reason… my customers always come back and i like my bleeders broke loose…can not stand stuck bleeders… but anyway bleed your brakes and you should be fine.. but if you still seem to be sluggish i would check for a sticking caliper after driving a short while feel the wheel see if it is abnormaly hot if so that is the one sticking…. i may not be correct in my diagnosis but this system seems to work for me

[Trent “Teddy” Martin]

Ok I’m young and stupid and crazy… But that’s not a bad thing it can lead to good things haha. I’ve learn that you can blow seals within the master cylinder if you push back a piston with the bleed nipple open it closed. The best and safest way to replace brake pads is to use a hose clamp and clamp the hose as close to the caliper as possible and crack the nipple. Them use a push back tool to push all the fluid out of the nipple this makes it easier to push back the piston and doesnt risk causing damage to any parts. Another trick is to use a vacuum bleed tool to pull the piston back :-). If you’d like me to make a video just say so I’d be more then happy too. This way also stops air from sneaking into the system 🙂

[Trent “Teddy” Martin]

And… To answer your question you either have air in the system or have damaged your master cylinder causing drag.

[dave]

Another trick is to use a vacuum bleed tool to pull the piston back .

Never thought of this…. i’m gonna try this in our brakes lab Tuesday. 🙂

very cool B)

[Trent “Teddy” Martin]

Just remember your clamps people! Haha and when your done remove the clamp crack the nipple and gravity bleed until no air. 🙂 Best pedal you’ll ever get

[Author]

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