Brake pedal spongy went down to floor, brake is ineffective and scraping noise

prav · **December 10, 2019, 09:05:33**

Hi,

Good morning.

I am using Hyundai i30 2018 model (in UK) which is fairly new under 30,000 miles. From last one month rarely I am noticing spongy brakes i.e., brake pedal going down all the way to floor and brake is ineffective i.e., car doesn't stop and also heard some scraping noise on the ground. In the first 2 instances I myself didn't believe that kind of thing happening but last week I clearly noticed these symptoms and felt very scary, good thing at that point is not much traffic and enough gap to the front vehile near small round about. The brake worked fine when it has comeup basically it's rare behavior but it is dangerous depends on the situation we are in. Given the stress one can get into with such situation, I have reported issue to Hyundai recovery where they kindly took the car to garage but surprisingly I heard from them in 3 days (including weekend) that no issue found and it's safe to drive on road as it was looked at by highly trained Hyundai technicians. I felt shocked to hear that such serious issue was not taken up very seriously instead asked to collect the car immediately. I had couple of discussion with both garage and Hyundai Service end up with collecting the car as they don't even talk about the problem instead they only talk about what they have done. No explanation on why brake pedal gone spongy & ineffective while driving, no explanation about the scraping sound. They kindly suggested to go for second opinion. At the moment left the car at home until I get it checked up by other party.

Please let me know if anyone has gone into similar problem or any suggestions on moving forward would be great help. Thanks.

CraigB · **Reply #1: December 10, 2019, 09:58:40**

If you feel there is still an issue then do as suggested and get a second opinion from a reputable brake specialist, if anything found then return to Hyundai with written report.

prav · **Reply #2: December 10, 2019, 10:08:15**

Thank you Craig, sure I am going to second opinion as I still feel there is an issue and garage couldn't find any (though I don't understand the procedures followed to identify rare critical issues).

Dazzler · **Reply #3: December 10, 2019, 21:07:44**

Welcome Prav,

Sorry to hear this. Very frustrating they were unable to identify an issue. You are doing the right thing. Hope it can be sorted without you being too much out of pocket.

Intermittent problems are the worst! So hard to diagnose and fix!

nzenigma · **Reply #4: December 11, 2019, 00:33:29**

Quote from: prav on December 10, 2019, 09:05:33

OK for 30k miles now noticing spongy brakes i.e.,

brake pedal going down all the way to floor and brake is ineffective,,,,,,,, then is OK

also heard some scraping noise on the ground.

Not trying to be smart but it is winter, possibly ice on the road.?

A driver inexperienced with black ice will have a wild ride and even wilder stories.

mickd · **Reply #5: December 11, 2019, 05:50:49**

@prav
Get it writing that all is good -just in case it's not

nzenigma · **Reply #6: December 11, 2019, 07:49:26**

Quote from: mickd on December 11, 2019, 05:50:49

@prav
Get it writing that all is good -just in case it's not

Not Winter?

prav · **Reply #7: December 11, 2019, 08:52:17**

@ Dazzler, Thanks, it is indeed nightmare as it takes lots of time, effort but no easy win...

Thanks mickd. Yes that's exactly i am trying to get from them. The loophole in the system is, we don't get to see whether the issue we reported has been taken correctly or not because we don't get to see what they have got on their system. When I asked for paper work, initially they said no paper work it's all in the system (which they can see not we) and we don't give any. And after asking again, they typed few points in front of me and put the sentence at end as "No fault found at time of test", this shows either they are not acknowledging the issue or don't even know what issue is. I only asked one question why did brake pedal go spongy all the way to the floor while driving, answer is it can't happen and parallel discussion starts saying it's all tested and good. I suspect they may not be believing in customer reported issue.

@ nzenigma luckily not full winter yet still see 2 digits sometimes, any way not too far from snow i think....

mickd · **Reply #8: December 11, 2019, 10:11:58**

Quote from: nzenigma on December 11, 2019, 07:49:26

Quote from: mickd on December 11, 2019, 05:50:49
@prav
Get it writing that all is good -just in case it's not

Not Winter?

Funny bugger

I Need new pic of Jimbo for your avatar please

prav · **Reply #9: December 11, 2019, 18:05:52**

After another round of e-mail discussion, I have been told by Hyundai service that this could be because of ABS kicking in and when ABS comes into picture causes scraping noise (which is definitely panic). Does anyone has experienced ABS behavior to be creating scraping noise and spongy brake?

nzenigma · **Reply #10: December 11, 2019, 20:27:37**

Quote from: prav on December 11, 2019, 18:05:52

After another round of e-mail discussion, I have been told by Hyundai service that this could be because of ABS kicking in and when ABS comes into picture causes scraping noise (which is definitely panic). Does anyone has experienced ABS behavior to be creating scraping noise and spongy brake?

Essentially your ABS is able to functional all the time. When the brakes are applied, especially when applied hard, the ABS backs the hydraulic pressure off sufficiently to allow the wheels to keep rotating.
You may feel the pedal pumping slightly. Thats all, no pedal to floor or scraping.
Would be interested to hear their explanation of the scrape. What part and how?

Dazzler · **Reply #11: December 11, 2019, 20:50:55**

Quote from: nzenigma on December 11, 2019, 20:27:37

Quote from: prav on December 11, 2019, 18:05:52
After another round of e-mail discussion, I have been told by Hyundai service that this could be because of ABS kicking in and when ABS comes into picture causes scraping noise (which is definitely panic). Does anyone has experienced ABS behavior to be creating scraping noise and spongy brake?

Essentially your ABS is able to functional all the time. When the brakes are applied, especially when applied hard, the ABS backs the hydraulic pressure off sufficiently to allow the wheels to keep rotating.
You may feel the pedal pumping slightly. Thats all, no pedal to floor or scraping.
Would be interested to hear their explanation of the scrape. What part and how?

There can be a bit of a clatter (but certainly no scraping noises)

nzenigma · **Reply #12: December 11, 2019, 21:26:22**

I notice that Prav has found another thread

2012 i30 brake failure

Unfortunately, the original OP gave us little useful feed back and then disappeared.

In both cases, the OPs have said the pedal has gone to the floor. This would mean that the system's hydraulic fluid has 1. disappeared somewhere or 2. has taken in air. Miraculously, the brakes recover (back to normal) for long periods.

This is excerpt is from two independent sources:

“In certain cases, when the ABS module fails, the brake pedal may become unresponsive. Usually the brake pedal will become increasingly hard to press until it is no longer responsive… The most common sign of an issue with the ABS system is the ABS Light coming on.”

In the two threads mentioned, the expected hard pedal and warning light are not mentioned .

Surferdude · **Reply #13: December 11, 2019, 22:10:49**

Quote from: nzenigma on December 11, 2019, 21:26:22

I notice that Prav has found another thread

2012 i30 brake failure

Unfortunately, the original OP gave us little useful feed back and then disappeared.

In both cases, the OPs have said the pedal has gone to the floor. This would mean that the system's hydraulic fluid has 1. disappeared somewhere or 2. has taken in air. Miraculously, the brakes recover (back to normal) for long periods.

This is excerpt is from two independent sources:

“In certain cases, when the ABS module fails, the brake pedal may become unresponsive. Usually the brake pedal will become increasingly hard to press until it is no longer responsive… The most common sign of an issue with the ABS system is the ABS Light coming on.”

In the two threads mentioned, the expected hard pedal and warning light are not mentioned .

I have to admit to not keeping up with brake design in recent years but my memory is that with a split system, a failure will see the pedal go closer to the floor but still provide retardation. And once it's failed, apart from pumping up while there's still fluid in the reservoir, you won't get the pedal back to normal.
Has something changed in the last 15 years?

nzenigma · **Reply #14: December 11, 2019, 22:57:15**

Same principle mate. More electronic sensors. 15 years ago, cars had ABS. Its still a split system, often diagonal rather than front and back, but still only half the brakes can fail.

Surferdude · **Reply #15: December 12, 2019, 01:12:45**

Quote from: nzenigma on December 11, 2019, 22:57:15

Same principle mate. More electronic sensors. 15 years ago, cars had ABS. Its still a split system, often diagonal rather than front and back, but still only half the brakes can fail.

Yeah. The ABS wasn't what I was talking about.
I'd forgotten about front or back split systems.
Only really knew diagonal.

Thanks mate.

Just on ABS, I reckon no one should be allowed to drive an ABS car until they've been given an experience of them working.
Take the car out on a wet road (tarmac preferable than just a loose surface) and jump on the brakes.
In my experience, most people who have ABS activate for the first time in an emergency, immediately lift their foot off the pedal when the judder kicks in.

Dazzler · **Reply #16: December 12, 2019, 08:20:26**

So in summary, Prav is adamant that the brake system failed and performed/ underperformed in the way described.

Our experienced members are basically saying such a failure then recovery with a modern split system is impossible. The dealer (after inspection) is basically saying the same thing.

I do sympathize with you Prav. This weird situation may be rare and not easily explained but there have now been 4 very similar occurrences reported.

I call that stalemate and not much either side can say or do until the mystery is solved.

I've just sent a message to member @Weenan who commented on that other thread to see if they got their issue sorted...

nzenigma · **Reply #17: December 12, 2019, 08:28:02**

Thanks Dazz

Hope we or them can solve this.

prav · **Reply #18: December 12, 2019, 08:34:47**

Yes exactly, including latest points from Hyundai mentioning ABS. My questions is around (a) pedal to floor (b) scraping noise (c) why ABS kicking in intermittently in normal conditions -- no wet road/ no icy/ no emergency braking

prav · **Reply #19: December 12, 2019, 08:48:18**

Thanks Dazz. You are right that the issue happening intermittently in no special conditions makes me to worry whether the sequence of things I have noticed are ok or not.
Actually I would be happily gave up if I was told initially either by garage or Hyundai service that this is normal scenario. But both garage and Hyundai service initially mentioned that this should never happen and yesterday I am given new info about ABS. I also gathered similar info from friends and colleagues that if the issue is intermittent then it must be ABS but I am also exploring whether ABS can kick in in normal conditions...

I would be more than happy if it is normal behavior.

I have noticed couple of links in on the same

i30 2015 brake failure

2012 i30 brake failure

Hopefully I will get this solved soon...

Weenan · **Reply #20: December 12, 2019, 08:59:46**

Hi there,
To resolve the issue I had to have the break master cylinder replaced, an independent garge I go to did this for me as he found the fault was a leak from one of the seals on the master cylinder.
The Hyundai garage couldn't find the fault as they said it was intermittent, however they obviously never looked at the master cylinder for fluid leaks.
Any way it has been done for over a year now and no more problems.
The master cylinder has to be replaced as the seals can't be replaced.
It cost me around £350 with my garage, however Hyundai wanted that just to inspect the car until i kicked up a fuss.
Hope this helps

Dazzler · **Reply #21: December 12, 2019, 09:13:21**

Brilliant @Weenan thanks again!

prav · **Reply #22: December 12, 2019, 09:19:43**

Thank you Weenan for posting the resolution that helped to solve the issue. I will ask the garage to look master cylinder by explaining the issue. Yes Hyundai service despite of warranty they are very reluctant to take up this instead they concluded all usual checks look good.

Thanks again.

nzenigma · **Reply #23: December 12, 2019, 20:20:22**

@Weenan

Thanks for your input. Glad a dangerous component was replaced for you.

I will add that many owners find an experienced independent workshop to be of far more value than their dealer.

In your case, was fluid found to be leaking to the outside of the master cylinder?

This wetness would be a normal check I would make under the circumstances. However, mechanics used by Prav and another complainant have never mentioned external leaks.

Cheers G.

Weenan · **Reply #24: December 12, 2019, 20:49:30**

Yes the fluid was leaking around one of the seals.
I did check the master cylinder myself before taking it in and noticed that the fluid level had droppec a little, however I didn't check for a leak with paper or a cloth.
The Hyundai garage couldn't find it because it didn't show up on the obd diagnostic reader, and they probably didn't know how to realease the bonnet catch.

nzenigma · **Reply #25: December 12, 2019, 21:27:29**

Thanks for the clarification mate.

Lift a bonnet? Outrageous!

Dazzler · **Reply #26: December 12, 2019, 21:38:55**

Quote from: Weenan on December 12, 2019, 20:49:30

The Hyundai garage couldn't find it because it didn't show up on the obd diagnostic reader, and they probably didn't know how to realease the bonnet catch.

Love it!

nzenigma · **Reply #27: December 12, 2019, 21:40:23**

@prav

Mate, Weenan has indirectly confirmed what I have mentioned here and elsewhere about brake hydraulics being a sealed system. Air being drawn in by a failed seal will displace the fluid, pumping the pedal will temporarily fill the void.

Forget that ratshit dealer for the moment. You need to make sure your garage has taken the trouble check for leaks, especially under the dash where the pedal contacts the master cylinder.

If its all dry, then we are back to square one.

nzenigma · **Reply #28: December 12, 2019, 21:43:40**

Quote from: Dazzler on December 12, 2019, 21:38:55

Quote from: Weenan on December 12, 2019, 20:49:30
The Hyundai garage couldn't find it because it didn't show up on the obd diagnostic reader, and they probably didn't know how to realease the bonnet catch.

Love it!

OOOH! you'll be banned.

prav · **Reply #29: December 12, 2019, 22:24:27**

Thanks nzenigma for the pointers and thinking ahead which I started thinking in similar lines. Yes agree that I shouldn't be relying on Hyundai service anymore. Now in the process of identifying experienced garage locally. Based on the suggestions, I have got everything in writing what they did and this what they mentioned "Checked All Brake lines and fluid level, no leaks present, tested brakes on MOT brake rollers all ok".
If we were to believe in what they did, there are no leaks including master cylinder then the issue is back to square one and my focus goes towards ABS. I have been reading some articles/posts which mentions about ABS kicking in at lower speeds and unwanted ABS activation.

Just for everyone to be aware how Hyundai service seems to be working from my experience in the past week, rather than resolving our concerns (so far not even single comment on the concerns raised) they simply suggest to go for second opinion and get back, it's bit of cheating because if we diagnose Hyundai issues what exactly they will be for.