Been having a brake problem recently with my vRS, when driving it'll suddenly feel like there is a loss of power, the car will nose drive when i'm off the throttle and the brake pedal rock solid. If I stamp on the brake pedal everything returns to normal for a time, this will happen randomly not after a journey of no or heavy braking. I've also been getting rather poor economy, 35mpg on the motorway at cruising speed, town driving doesn't improve or worsen this. Is this likely to be brake servo/vacuum hose or something else?

Brake system sounds like it's holding pressure in the brake lines. Are the wheels getting hotter than normal? To test servo, ignition off, pump brake pedal to deplete vacuum, pedal should go rock solid. Keep pressure on pedal and start engine, pedal should move down a few inches. If servo is OK suspect master cylinder.

The n/s/f and o/s/r were far hotter than the other corners - the brake discs were also too hot to touch whereas the other corners were only warm - i'll try the pedal test you've suggested when i leave for work.

Did the servo test - with ignition off can pump the pedal a couple of times it then goes rock solid, (the same as what randomly happens when I driving) - started it up with the pedal pressed, it then slowly sunk down, did it 3 times with exactly the same result, i guess it dropped to between half and 2 3rd of the way to the floor. Whilst sat at 70 this morning it happened again feel like something is dragging/excessive air resistance (like driving through treacle) after a couple of minutes of that there was a sound coming from atleast one brake disc like it was overheating, when I slowed down this sound got better like the disc was cooling.

Stupid question I guess, but will ask anyway - is it best to buy a new master cylinder? Have found a second-hand one on ebay for £30 but that's got an unknown life expectancy.

Should I wish to upgrade the brakes (the standard one never felt much cop in the 3 years i've had it) in the future would it be better to put a bigger master cylinder or is that man enough for bigger brakes (up to a point)?

Edited 12 August, 201114 yr by xxzantrix

Never fit brake parts from e-bay, just not worth the risk. Have calipers checked first, the dust seals can go hard and prevent the pistons returning fully. You could also have a faulty flexible pipe acting as a one way valve. I would have the fault traced by a brake specialist to pin point the problem and go from there.

It's in the garage at the moment... was going to have the caliper replaced as the O/S front would not turn freely, as soon as it was jacked up this morning, the N/S front won't turn freely but the O/S front wheel, then not long after neither would turn freely - not convinced this is a caliper problem as it seems to shift between sides. Looking into the fauly fleixble pipe at present. Any other ideas short of booking it in to the main dealer to diagnose the fault?

i am also of the opinion my life is worth more than any cost saving of using second hand or cheap pattern parts for brakes

It's in the garage at the moment... was going to have the caliper replaced as the O/S front would not turn freely, as soon as it was jacked up this morning, the N/S front won't turn freely but the O/S front wheel, then not long after neither would turn freely - not convinced this is a caliper problem as it seems to shift between sides. Looking into the fauly fleixble pipe at present. Any other ideas short of booking it in to the main dealer to diagnose the fault?

If discs getting hot then they are defo sticking "on". If pipes are all ok inc flexi then???

Depends how mush work you like doing yourself!!! If like me you like????? doing it yourself and have tools and a Haynes then strip each caliper and replace dust skirt and inner seal and re-copper-grease slides, pad backs, etc. Then rebleed using a pressure bleeder the whole system......process of elimination I'm afraid!!

If discs getting hot then they are defo sticking "on". If pipes are all ok inc flexi then???

Depends how mush work you like doing yourself!!! If like me you like????? doing it yourself and have tools and a Haynes then strip each caliper and replace dust skirt and inner seal and re-copper-grease slides, pad backs, etc. Then rebleed using a pressure bleeder the whole system......process of elimination I'm afraid!!

Not only do the disc's get hot the tyres get noticably hot also, I agree something is sticking though is it "usual" for the sitcking to intermittantly alternate between the front calipers? No heard any more on the flexible pipe so it may yet still be that.

If I had the correct tools perhaps i'd dismantle it myself, just the tool for winding back in the brake pistons didn't appear to be too cheap last time I looked.. then again as I'd have no idea what I'm doing (I can probably just about identify all the parts you've listed above) not sure I could trust myself to put it back together properly.

Failing that.. anyone want to buy it? :think:

If I had the correct tools perhaps i'd dismantle it myself, just the tool for winding back in the brake pistons didn't appear to be too cheap last time I looked.. then again as I'd have no idea what I'm doing (I can probably just about identify all the parts you've listed above) not sure I could trust myself to put it back together properly.

Failing that.. anyone want to buy it? :think:

Windback tool is about £18 (laser 3128???? not 100%).....I ended up teaching myself with a Haynes...just took my time studying it etc!!!

Windback tool is about £18 (laser 3128???? not 100%).....I ended up teaching myself with a Haynes...just took my time studying it etc!!!

As little as that, perhaps I was looking at a different one.. i recall it having 10 or 12 different sizes presumably for different cars? The money i'd save on discs and pads alone would be suprising i'm sure.

No fault found with any of the pipes either, strangly it seems fine now, much less hesitant i.e. no drag from any brakes - took for a motorway run, no noise coming from the discs now. Releasing the thottle doesn't cause it to nose dive (whereas it was on a downhill out of gear yesterday)... solution was to change the brake fluid (which I suggested when I dropped it off as i'm fairly certain it's not be changed since I've owned it), how does that work? will see how it goes over the next week (the problems occured everytime i've driven it recently)

...spoke too soon.. two days later and the problem is back, not so severe but back all the same

Time to start dismantling the braking system i guess :think:

Update: Problem is back to how it was last week, it seems the warmer the day the worse it is...

Have ordered a brake piston winding tool, expecting delivery at some point tomorrow - assuming I can get hold of the dust skirts and inner seal in time i'll have bash at cleaning them up on Monday

..if that fails 312mm brake upgrade and/or master cylinder time (cost of buying two new standard calipers, carriers, discs and pads is more than a refurbed 312mm kit with new discs and pads) .

Replaced all seals on the front calipers.

The bottom slider O/S had near enough seized due to the small rubber seal going hard, new seal allowed this to again move

There was no seal on the N/S bottom slider which too was not moving freely.

Piston seals had seen better days so replaced those too

Both sets of Front pads had plently of meat left on them, discs are quite worn but don't appear to need replacement just yet.

There is a noise still then turning the discs by hand (they move freely) not sure if there is where the pads sit so close to the disc.

Drove absolutely fine yesterday, but again today it's not right, was sat on a slight incline without the footbrake or handbrake and it would not roll back as i'd have expected, economy is poor 270 miles from a 'full' tank and at speeds of 60mph and higher there is a noise coming from one of the corners.

I've jacked up the back today and the discs and pads are very worn (will replace in the next few weeks) but didn't have time to start ripping those apart).

Because the front pads and discs both have equal wear it's got to be either both are intermittently sticking or there is nothing wrong with the fronts per sé? (the noise which appears to be coming from the O/S front disc may be a wheeling bearing/or infact coming from somewhere else)

If the servo was faulty I'd lose presure when pumping the brakes with the engine off (though is test near enough 100% guaranteed to be used as gosple)?

The symptoms I'm having don't seem to be consistant with a Master cylinder fault (this doesn't mean it's not that).

Garage couldn't find any fault with the brakes... if anyone lives this way could you recommend a brakes specialist?

Any other thoughts on this?

I know it's some time after this was first posted but I have a similar problem with my 05 reg VRS (N/S/F and O/S/R discs getting hot). Calipers etc checked and OK. Wondered if you'd managed to get a satisfactory answer to the problem? It's driving me mad! Thanks.

I seemed to have this problem (O/S/F & N/S/R discs getting hot) on my 2005 Octavia 1.9TDi.

 

This was after rear pads and rear calipers renewed. Handbrake cable was also freed up and working OK. All four discs and front pads had been renewed the previous year.

 

There may have been more than one issue, because the orange brake pad [()] warning light was on & off intermittently.

 

Front o/s pads removed and caliper slides cleaned up (& copperslip). May have been grit or other debris on pads cleared by this and hard braking.

 

It has been mentioned on the forum that, when changing the calipers (& therefore bleeding some fluid out of them), air could have got into the ABS block, if the fluid level in the master cylinder became too low. Therefore brake fluid also changed at VAG independent (£40). I assume this was done in the recommended way as described elsewhere on the forum - i.e. with VCDS plugged in, and bled from all four calipers + two bleed nipples below the master cylinder.

 

Anyway, seems to be better now.

Hope this helps

The n/s/f and o/s/r were far hotter than the other corners - the brake discs were also too hot to touch whereas the other corners were only warm - i'll try the pedal test you've suggested when i leave for work.

  I would be looking for a collapsed flex pipe first