[Ogi]

Now i have a different problem!! While changing the wheel thread (other topic i made) they had to remove the whole brake system from the rear right wheel. After they mounted it again, i heard (maybe it started before but i haven't hard it!) strange sound when i press brake, it's like when you press a pump for a tire for exampe, it's the sound of suppressing air !! I hope you understand !!

What wrong now ???? 

[syecadelic]

not a clue 

but i'd take it back to the garage and get them to look into, why did they have to remove the breaking system for changing the wheel.. or is this reason mentioned in your other thread ?

[Ogi]

Yes, that is the reason, they didn't change the wheel but what i described and post a photo in that other topic.

[Phil №❶]

Ogi,

Did they replace the whole hub, or just fix the broken stud on your hub 

Does this sound remain while you're braking or just when you apply the brakes 

Does the braking feel normal and even when braking 

[Dazzler]

Sounds like you will definitely need to go back Ogi  (you can't take a risk with your brakes)

[Asterix]

If it's air pressure you can hear, than it's not from the rear brakes.

The only place there's compressed air regarding the brakes is at the master brake booster.

The brake booster get the vacuum form the engine.

You can sometimes hear the vacuum when you press the brakepedal, it's normally no problem, but have your garage check it out.

The old saying that if you keep pressing the brake pedal with engine idling, the pedal must not go further down, is not valid on modern diesels. There's so much vacuum, that if you keep pressing the brake pedal, the pedal will slowly move further down.



(Master brake booster is no 3 on pic in the link)

http://www.google.dk/imgres?q=bremseforst

[Surferdude]

Certainly go back and get them to look at it. I'm wondering if it's just a brakepad not quite located properly and scraping on the rotor. If so, it will go away when you take your foot off the brake pedal (or if it's there when you're not braking, it should go away when you apply pedal pressure).

[Ogi]

Asterix, i am afraid you are right. Just got back from outside, i wanted to hear where is that sound coming from and it's coming from just behind the brake pedal! There is a pedal, than the bar going down from the pedal to the engine room, that bar enters the rubber cuff and there's some sponge in the cuff as i could see. Thats where that sound is coming from! I think that is the vacuum part you were talking about.

[Asterix]

No reason to be afraid.

If you have any doubt, let the garage check it out, but I'm pretty sure nothing is wrong.

[babis_xo]

I can hear a similar sound and I'm sure it's from rear. Feels like a normal sound though, what else could it be besides "pressurized air"?

[Asterix]

Hi Babis

I really can't think of anything from the rear that could sound similar to previous mentioned, but I will keep you in mind.

Is it only present when you press the brake.. If it is, can you have someone to press the brake and the you listen different places in the car to locate the sound.

[babis_xo]

Yes it's strictly related with the pedal pressing and noise varies depending the pressure force.
Maybe you're right, I'll have someone else to press the brake

[Ogi]

It's OK sound!!   Every Hyundai i tried have the same sound. It has something to do with the powerbrake system...

[babis_xo]

It's OK sound!!

[kabukiman]

Now i have a different problem!! While changing the wheel thread (other topic i made) they had to remove the whole brake system from the rear right wheel. After they mounted it again, i heard (maybe it started before but i haven't hard it!) strange sound when i press brake, it's like when you press a pump for a tire for exampe, it's the sound of suppressing air !! I hope you understand !!

What wrong now ???? 

mine makes a kind of hissing noise like that every time I start the car, the first time I press it.  The car is a week old, I don't think it's a problem.  The brakes still work, there's still pressure, the fluid is still moving.

If you press the pedal and it's spongy and nothing happens, then you've got something to worry about.