Last week I took my octavia (1.9 turbo diesel) for it's MOT, it failed on the brake pedal going straight to the floor. I found the problem the hand brake lever on the rear shoes had seized and the rear brake cylinder had sprung a leak.

With this fixed and the brakes bled, can someone confirm that the pedal should continue to creep to the floor when the engine is running and remain hard when it isn't.

thanks

I have disks on the back of my TDi, but I know that with the engine running my foot will gradually sink to the floor.

This should NOT happen. You have a seal passing in your system somewhere.

Thanks

I thought that was the case, I will book the car back in tomorrow.

mmmm, mine went into a skoda dealer for this and they told me it was normal behaviour.

I've got a 110 TDi too and mine doesn't do it. It should feel firm with the engine running.

How long does it take to reach the floor? If we're talking seconds then you need to get it looked at straight away.

IIRC, this could be a sign of a faulty non-return valve at the servo.

mmmm, mine went into a skoda dealer for this and they told me it was normal behaviour.

In that case i would call Skoda UK - tell them what a bunch of lazy cowboys they are at this dealer and NEVER go there again!

In that case i would call Skoda UK - tell them what a bunch of lazy cowboys they are at this dealer and NEVER go there again!

:iagree: wholeheartedly. This is not correct behaviour for a car with a vacumn servo (in extreme cases of persistent heavy use and low engine revs you might get the pedal to go up as you run out of vacumn though).

I spoke to my mot man yesterday and he said if you put your foot on the pedal and start the engine the pedal should drop slightly but should still feel firm.

I am going to bleed the brakes again and go from there.

I spoke to my mot man yesterday and he said if you put your foot on the pedal and start the engine the pedal should drop slightly but should still feel firm.

I am going to bleed the brakes again and go from there.

He's right. When the servo starts working the pedal should drop slightly, but then stop.

I spoke to my mot man yesterday and he said if you put your foot on the pedal and start the engine the pedal should drop slightly but should still feel firm.

I am going to bleed the brakes again and go from there.

I read your OP as meaning that, if you start the engine, then put your foot on the brake pedal and leave it there, the pedal eventually sinks to the floor. If that's an accurate desciption of what happens, I think you've got a fault with the master cylinder seals.

Edited 7 November, 200817 yr by KenONeill

:orb_bonk:

I'm with Ken on this.

The pedel must not drop under a given consistant load with the engine running or not.

If you have your foot on the brake then start the engine of course the pedal will drop a bit then stop with the servo assistance. But surely this does not relate to the first post?

In that case i would call Skoda UK - tell them what a bunch of lazy cowboys they are at this dealer and NEVER go there again!

They did a fluid change a the same time as well - this was 2 years ago or so.

Ok bled the brakes. A definite improvement but if you really press hard it will creep very slowly to the floor.(approx 10 seconds) Not happy with the feel so someone scare me, how much will a master cylinder set me back and where is the best place to get one from.

i'll time mine and see how long it takes to sink to floor level.

Ok bled the brakes. A definite improvement but if you really press hard it will creep very slowly to the floor.(approx 10 seconds) Not happy with the feel so someone scare me, how much will a master cylinder set me back and where is the best place to get one from.

Deffo not right -creep to floor smacks of fluid loss. How sure are you of master cyl - seals going -possibility of fluid sucked into engine - clue -lots of white smoke out of exhaust . Otherwise - have you any wet patches on wheels (around brake bits ) ,or any signs of fluid loss under car /

There are no puddles on the floor and I have not seen any white smoke.

I have been round the car a number of times and can't see any leeks, the reservoir does not seem to be going down either.

The only thing I can think of is one of the seals in the master cylinder just passing slightly as the vacuum assists with braking.

Any comments....

Deffo not right -creep to floor smacks of fluid loss. How sure are you of master cyl - seals going -possibility of fluid sucked into engine - clue -lots of white smoke out of exhaust . Otherwise - have you any wet patches on wheels (around brake bits ) ,or any signs of fluid loss under car /

Are you sugesting the possibility of brake fluid going into the engine - you clearly know nothing about the brake system on a car!! :eek:

Defo an internal seal passing somewhere hence no fluid loss (i'm not going to put my head on the blocks and say where)

[Defo an internal seal passing somewhere hence no fluid loss (i'm not going to put my head on the blocks and say where)

That was my thinking, but the only places it could pass without leaking fluid onto the floor is the master cylinder or the ABS block.

Surly the master cylinder is the cheaper option, any prices ???

VW Golf Mk 4 Bora AUDI A3 TT Brake Master Cylinder NEW on eBay, also, Volkswagen, Car Parts, Cars, Parts Vehicles (end time 19-Nov-08 16:12:10 GMT)

Don't know if this is the exact one as on the Octavia but it does list a part number and all you need to do is call the service department at your local Skoda dealer to confirm if it will fit.

I just thought I would give everyone an update.

I took the car back today and it passed, in the end I did a complete brake bleed. Starting at the master cylinder and finishing at the rear wheel.

Now when I start the engine the pedal will drop slightly and then remain firm, pesky air.

The cheapest master cylinder I found was from :-

Skoda Parts, Original Skoda Parts Online, International Delivery They quoted me £54 including VAT and postage, I thought that was quite good.

Thanks to all for your advise

Pesky air, and lots of it from what you say!

Further thought which I'll put here for the benefit of future searchers. If you've got enough air in the system for the pedal to sink rather than just feel spongy, once you've evacuated the servo, the pedal should sink under steady pressure with the engine off as well as on.