Hi All,

 

I have a 2007 Scout.  For a year or so it ran superbly.  Then, a year or so ago, I stopped at a motorway service, got out, smelled hot friction material, found the front nearside wheel (only) was very hot: too hot to touch.  Took it to garage my (trusted local independent) who replaced the caliper on that corner, and pads on both fronts.

 

However, various problems since then:

 

• An intermittent ringing noise, sometimes quite loud, apparently coming from the front of the car.  Noise would fade in gradually, then sometimes fade out on its own.  Could be stopped (temporarily) by just the very lightest dab on the brake pedal.  Over the course of a few months the intermittent ringing noise faded and eventually disappeared.
• After some months of silent running, gradual appearance of an intermittent rattling noise.  Could be stopped (temporarily) by just the very lightest dab on the brake pedal.  Over the course of a few months the intermittent rattling noise faded and eventually disappeared.
• Occasional noticeable warming of the front wheels, sometimes one side, sometimes the other.  Never so hot as the original problem.
• Intermittent sticking of the handbrake, causing problems such as stalling when hill-starting.
• Intermittent release of the handbrake without warning, causing problems such as damage, fortunately only to my car, in pub car parks.
• And finally, persistent soft brake pedal with disconcertingly long travel.  The pedal was fine before all of these problems, but now it is soft, lacks feel, and is rather alarming when you come up behind another car at a junction.  To be clear, the brakes always work...but you often wonder whether this time, maybe they won't.  If you pump the pedal, it hardens up.

 

So, in the past year or so almost the whole of the braking system has been replaced: calipers, pads, master cylinder, handbrake cable.  None of it seems to have made any difference.  As well as my trusted independent I have taken it to the local main dealer, and to another independent specialist in VAG cars.  The system has been bled repeatedly by all of them, and they all acknowledge the pedal is too soft.  The independent VAG specialist says he has "seen it before" but can't suggest any solution.

 

Any thoughts?

 

Cheers,

 

scandalxk

Edited 9 May, 20206 yr by scandalxk

$

This is probably not going to make you feel any better.

 

I had this problem on my 2010 FL Scout.

 

My main issue was with the OSF, at one point it got so hot it blistered the powder coating on my alloy.  I also began to experience intermittent issues with both rear wheels.

 

IIRC, over an 18 month or so period I had to replace all four brake pads and discs (both rear twice)  and 3 of the calipers (at least one of the rears twice). I even had the brakes stripped, cleaned and regreased(?) at my local Skoda dealer.  All worked as they should for a few months before the issue returned.

 

It only seemed to get resolved when I took it to an Audi specialist who replaced all four brake pads and discs and at least one of the rear calipers. 

 

He stated the items fitted by the local garage (which the Skoda dealership stated were fine and only needed a clean) were not up to the task.

 

When I asked why it kept happening I was told by each there was nothing obvious that they could identify as causing the issue., "sometimes these things happen"! 

 

The brakes and handbrake always worked,  and the brake pedal always felt normal.  It even passed two MoT's, and had two services carried out without any comment being made about the brakes or their operation during this period. 

 

The total cost of repair, around £1500, the niggling doubt that it could return were the main reasons I traded in my Scout in March of this year. 

 

However, it did seem that replacing the parts with more 'premium' items did resolve it: I drove from Glasgow to Gairloch in the Highlands and Glasgow to Chester shortly after without any repeat performances!

 

HTH

Edited 9 May, 20206 yr by FirstAndLastSkoda
FFS

Rattling noise could be the pads rattling in the calipers until dust and crap build up over time stopped them rattling.

 

Could the flexi brake hoses have been crimped maybe deforming the inside of them and stopping the brakes releasing fully, causing the heating effect? Could also be the build up of dust and crap making the pads stick in the caliper carriers.

 

You could strip and clean the calipers, carriers and pads and regrease carefully at the edges of the pads and slider points on the carriers to eliminate the pads sticking in the carriers. Also check that the pads fit and slide in the carriers ok and that they are not tight because of rust.

 

Also check the operation of the hand brake that it's not sticking at the pivots etc.

 

 

 

43 minutes ago, FatblokeVRS said:

Could the flexi brake hoses have been crimped maybe deforming the inside of them and stopping the brakes releasing fully,

 

It seems from what the OP said that pretty much all the braking components have been replaced - except for the flexi hoses?

Its regularly suggested on forums, so frequently that I think its become accepted by default as a fact rather than a hypothesis.

 

I have spent far too much time around cars, replaced lots of perished and/or failed brake hoses and had to resolve many many instances of binding brakes but have yet to encounter a collapsed hose being the culprit.

 

The closest I have ever experienced was a MK1 Mini with a really heavy clutch, I bought it as a scrap shell and the engine had been out for years, the steel hydraulic clutch pipe was severely corroded inside reducing the diameter, I diagnosed it as the fault because if the clutch was operated very slowly the force needed on the pedal was normal.

 

On reading the OP's description it made me think of one of the valves in the ABS block that can retain pressure on individual wheel brakes as part of one of the 3 letter acronym safety/stability systems, I read about it in the self study guide, it took a lot of understanding and I made a mental note that stickiness of the valve could cause some very undesirable and hard to diagnose braking faults especially brake drag on one wheel only.

 

The soft pedal would be a big warning sign to me.

 

It wont be related to the front wheel noises or dragging but the handbrake problems could explain the excess pedal travel which I think may be what you describe as a soft pedal. You need to remove the ashtray from the rear of the centre console to see the handbrake compensator, when the handbrake is applied it should be level and not cranked to one side, both cable adjusters should have equal threads showing, if not then its a big sign of an longtime problem with one of the rear calipers.

 

Look at the angle of the handbrake actuator levers on both calipers when handbrake applied, they should be even, then look when handbrake released, they should both return to the stop.

 

The rear caliper piston seals look symmetrical but they are not, fitting them the wrong way round stops the self adjustment mechanism working giving a long brake pedal and inneficient handbrake, people then adjust up one cable to compensate which can result in one rear brake dragging, I know this has not happened in your case.

 

It could be that you have 2 brake problems, the handbrake/long pedal if it is a rear caliper problem is easy to diagnose and repair leaving you hopefully with less symptoms for the front brake problem.

 

Finally it could be that the ABS system needs a proper forced purge bleed using VCDS which takes a long time and uses lots of fluid.

Edited 9 May, 20206 yr by J.R.

Thanks, all, for your interesting and useful comments.

 

My feeling is that there are at least two problems on the go here, probably because the original garage failed to fix problem one, and introduced problem two at the same time.

 

To reiterate, most of the braking system has been replaced with new, including all the calipers, all the pads, the master cylinder and the handbrake cable.  Also, all the discs (sorry, I forgot to mention that before).  The system has been bled several times, including the forced purge bleed.  The ABS "block" (?) and the flexible hoses have not been replaced.

 

I suspect that the intermittent ringing, followed (after an interval of silence) by the intermittent rattling, are probably the same thing, perhaps due to the pads rubbing on the discs, and causing the ringing like a finger running around the rim of a glass until they wore down a bit, then, after an interval, rattling in the housings when a bit of play has developed.  The reason I think so is that the way to stop it happening was identical in both cases: a very slight dab on the brake pedal.  But what do I know.  The rattling was still happening before lockdown and I suppose it probably will resume when I start using the car again.

 

I think that dirt or rust in the calipers are very unlikely, given that the problems continued after they were all replaced with new.

 

My cynical suspicion is that any criticism of Skoda (or aftermarket parts) by an Audi specialist is probably just snobbery!  😉😆 But thanks anyway. 🙂

 

J.R.'s post is very interesting.  What do you mean by the "ABS block"?  Is this a component containing control valves (presumably four) for the ABS?  Perhaps like this one on Ebay? "SKODA OCTAVIA ABS PUMP CONTROLLER MODULE HYDRAULIC BLOCK UNIT"  (That title seems to cover all options!)  As I understand it the valves control fluid pressure to each wheel individually, so I can see why this might cause some of my problems.

 

The other very interesting item in J.R.'s reply is the bit about the handbrake compensator.  I have just looked, and I see that the compensator is not straight - it is further forward on the left.  Unfortunately I can't remember the sequence of events in the car's many trips to the garages, but it could be that the soft (long travel) pedal arose after replacement of the rear calipers...perhaps...and perhaps they have fitted the rear caliper piston seals wrongly.

 

Thanks again, all.  I'll have a chat with the "VAG specialist" and see what he thinks.

 

scandalxk

You have a problem with the self adjusting mechanism on the left rear caliper, it will be witnessed by the angle of the hendbrake actuating lever compared to the other side in both the on and off position, also there will be slack in the LH cable when the handbrake is released.

I never actually resolved my rear caliper problem, I could see that it was not self adjusting like the other, that the piston did not have the free fore and aft  movement relative to the seal needed to engage the self adjust mech, reversing the seal worked but the problem returned, I decided to refurb the caliper and ordered seal kits but also 2 cheap Chinese calipers which I fitted to refurb the calipers at my leisure.

 

I never got around to refurbing them and passed them on to StickyMicky as the car has been replaced by a Yeti.

3 hours ago, J.R. said:

I never actually resolved my rear caliper problem...reversing the seal worked but the problem returned...

 

So, if the problem returned after you had reversed the seal, then presumably that was not the cause? 🤔

No the problem was definitely the self adjuster not working properly when in service, worked fine on test bench, 99% certain it is due to piston not having enough free(is) movement for the adjuster to work, initially it also exhibits brake drag.

 

When the handbrake compensator is angled like yours it means the piston only has to push a tiny amount on the good caliper to clamp the disc but a long way on the bad one, that gives the long pedal and the handbrake releasing etc that you have suffered.

 

You can manually advance the piston using a wind back tool in the opposite way it was intended, dont go to far or you could get brake bind, you will then have a good handbrake and solid brake pedal (assuming there is not air in the system) until the pads wear. Its a good way to be 100% sure or in my case to find out that I had not fixed the problem as I thought I had.

 

Before doing that make sure someone before you has not taken up slack on the LH cable as that will cause problems probably binding of the caliper.

2 hours ago, scandalxk said:

So, if the problem returned after you had reversed the seal, then presumably that was not the cause? 🤔

 

I will never know but the seals were quite swollen and also stretched having been removed a few times, also the piston may have started sticking in the bore etc, it was all working fine on the bench.

12 hours ago, scandalxk said:

My cynical suspicion is that any criticism of Skoda (or aftermarket parts) by an Audi specialist is probably just snobbery!  😉😆 But thanks anyway. 

You've misread my post, but good luck with your issues, regardless.

On 09/05/2020 at 23:35, J.R. said:

...

 

On reading the OP's description it made me think of one of the valves in the ABS block that can retain pressure on individual wheel brakes as part of one of the 3 letter acronym safety/stability systems, I read about it in the self study guide, it took a lot of understanding and I made a mental note that stickiness of the valve could cause some very undesirable and hard to diagnose braking faults especially brake drag on one wheel only.

 

The soft pedal would be a big warning sign to me.

...

 

Update:

 

I had the ABS block changed.  It has solved the long brake pedal travel and now the car is lovely to drive again.

 

Apparently the cost of a new replacement is £1,100 or thereabouts, but I got a used one from Ebay for £65.  A risk, but it seems to be OK.  And I could have taken that risk 16 times before I would have been out of pocket 🙂.

 

I haven't had a chance to drive the car a significant distance, so it remains to be seen whether the other problems persist.

 

Thanks for your help.

 

scandalxk