Hi,

Thanks for looking. 

I've got Fabia 1 mk2 1.2 HTP 44kw  60hp 2010.  Options codes attached.  What a great car.....  apart from the brakes.

I've been reading about similar issues across this and various VAG forums but I just wanted to see if my brake symptoms pointed to anything in particular before I spend more £££££ on it.  

When I bought the car I knew that it had been stood for 6 months.  The brakes were sharp and a bit noisy, but effective with a bit of play in the pedal.  

I first thought that a bit of use might smooth them out a bit and it was fine until the first motorway commute when they binded on both sides and were smoking.  

I removed the rust from both callipers, greased everything and checked the piston movement but the binding continued.  

At this point I had new hoses and callipers fitted which didn't fix it.  The travel in the pedal is more and things have improved, it can be better if I drive as mentioned below and I have not got to point of them smoking but they still bind.  It seems to start with the drivers side.  There's no drag to one side when driving when they start to bind or when braking.  

It binds after driving for a while without using the brake.  The pedal travel becomes less and the drag will get worse.  

It seems to reset the brakes if I get a chance to stop and press the pedal back down as far as it will go.  

I was originally doing a lot of engine braking and thought that avoiding the brakes as much as possible would stop them from heating but because I'm avoiding using the motorway (not many hard shoulders anymore) I've been in a lot of stop/start traffic and found that actually the more I use the brake, bring the car to a stop with it and hold it down when stationary it rolls smoothly, almost always free rolling when the brake is released and not loosing speed when coasting.....  but the binding will return if I have a long run (probably 5-10 miles) without using the brake.

Whenever I park up I check the discs for heat and the drivers front side is usually too hot to touch and the passengers side is variable from very hot to cool.  I haven't felt any heat from the rear drums.  I'm now on my 3rd full tank of petrol and I'm getting around 280 miles per tank.  

 

Before more major work starts I was wondering if these symptoms point towards anything in particular.  My mechanic (independent) is now thinking Master Cylinder, Servo, ABS pump.  It's due to go back in on Wednesday.

 

From what I've found it could be the servo vacuum hose?  Leak or faulty check valve?  I'm wondering if the fact that it seems to be one sided initially, could that rule out certain parts of the system as I imagine that before the diagonal circuits start any problems would affect both side equally?  Does the system split in the Master Cylinder?

 

The problem seems to build up as I drive.  Is it the heat build up that increases the system pressure which increases binding or could it be a gradual build up on long runs due to a vacuum leak issue (which then causes heat which just adds to the problem)?  

 

I've tried the various servo checks that I've found on here and everything seems ok in terms of the pedal response.

 

I was going to try the following:  check for leaks around the servo vacuum hose;  test the hose check valve as best I can (suck/blow test);  do some consistency checks by rolling on a hill and seeing if the brake release response is the same every time;  and would the response of the brakes, if I apply/release the brakes whilst my foot's on the accelerator, indicate anything (it does appear to drag and slowly release when I do this rather than a quick/definite on/off response).

 

Also, when the ABS kicks in does it sound like a fast clicking with very little stopping power?  This happened once in the snow when the brake pedal had stiffened up to the top and the brakes had become very sharp.  I've done some very hard stops on dry roads and this hasn't happened then.  

 

Thanks again.  Any advice gratefully received. 

 

Edited 8 July, 20196 yr by john999boy
Photo removed at OP's request.

Make friends with another mechanic, this one is failing badly to actually achieve what you want, a working brake system.

Will do.

He's a mechanic at the local independent garage that we've always used.  Not a friend that's just having a go.  

He has replaced the hoses (symptoms of internal collapse causing poor fluid return?) and later the calipers (symptoms of compromised pad return due to the car being sat for a long period?).  Failing badly is a bit harsh

OK sorry, not failing badly, just a little bit.  If you are happy to keep spending on not having the brakes work then you have the best mechanic for that.

There is a bit of a lottery to finding the fault straight away isn't there?  I've only ever used garage's to replace failing parts; straight swaps.  This situation is new to me.  

Could he have tried new hoses and callipers just to see if they fix the problem, and then put my old ones back on if they didn't?  Just charged for labour?  Cheers

Checking the servo vac hose is a good idea in general, as they are a bit prone to failure, but I'm not convinced it's causing this problem.

Wish I had more ideas about what is.

 

 

Once the brakes have started to bind do they release again over time i.e. next day no binding until you drive it again?

Thanks.  Is the fact that it's worse on the drivers side suggesting that it's not the vacuum hose?  

 

1 minute ago, CWARD said:

Once the brakes have started to bind do they release again over time i.e. next day no binding until you drive it again?

Generally the brakes are stuck on when i come to use the car the next day (95% on the time).

Once they're released and I start driving it's ok, sometimes slight rubbing noise on driver's side at slow speeds but no, or minimal drag, when coasting.  

It will then build up.  Thanks

How are you releasing the brakes?

 

sorry for all the questions but it helps 

Also, with it being a bit one sided, would it be worth checking the driver's side wheel bearings?  I'm not getting any obvious noises from it.

How obvious is a warped disc?  

(awwaofsk... I know that the mechanic should know this)

Just now, CWARD said:

How are you releasing the brakes?

 

sorry for all the questions but it helps 

No worries at all.  I appreciate the interest.

 

Sometimes it can be as little as rocking in my seat (which is what this problem is making me do), sometimes just finding the bite will be enough.

Prior to getting the hoses/callipers changed it could take a lot of bite to free them.  Thanks

When you do the rocking do you hear a click  or clunk when they release

12 minutes ago, CWARD said:

When you do the rocking do you hear a click  or clunk when they release

More of a clunk.  

You’ve cleaned up the original calipers before replacing them and the pipes. I assume the disc and pads are still the same.  If this is the case then remove the pads and file the tabs down a bit so you remove the burrs. They should fit into the anti rattle clips easier then. I had this problem with the Octavia brakes that would bind and it was nothing more than the pads fitting too tight due to the burrs not removed. Also ensure the sliding pins are only lightly greased. 

8 minutes ago, CWARD said:

You’ve cleaned up the original calipers before replacing them and the pipes. I assume the disc and pads are still the same.  If this is the case then remove the pads and file the tabs down a bit so you remove the burrs. They should fit into the anti rattle clips easier then. I had this problem with the Octavia brakes that would bind and it was nothing more than the pads fitting too tight due to the burrs not removed. Also ensure the sliding pins are only lightly greased. 

Ok thanks.  Will do.  

Yes the pads (fairly new looking) and discs are still the same.

I've only seen the pads off during the initial calliper clean up.    From a quick google image search they looked like this minus the cable.  

Which bits on the pads do you mean (sorry newb question)?

Thinking about it, It took a lot of effort to fit the pad back into it's holder on the outer face of the calliper.  No probs with the piston side.  

The tabs or ears on the left and right

Edited 18 March, 20188 yr by CWARD

Good to remove any rust from the surfaces that those tabs slide along too.

 

The reason I thought that the servo hose couldn't be involved is that absence of vacuum can make the servo do nothing, but cannot actually cause it to push on the master cylinder 'on its own' as far as I know.

2 hours ago, CWARD said:

The tabs or ears on the left and right

Brilliant. Thanks

2 hours ago, Wino said:

Good to remove any rust from the surfaces that those tabs slide along too.

 

The reason I thought that the servo hose couldn't be involved is that absence of vacuum can make the servo do nothing, but cannot actually cause it to push on the master cylinder 'on its own' as far as I know.

Ok thanks.  Hopefully those surfaces should be ok with them being new callipers.  That (and the new hoses) could be contributing to the symptoms being less severe since they were changed.  

 

I've been reading through various servo explanations... but i guess I've been clinging onto this being the problem due to it being a cheap solution to someone else on here!

My only thought was that the check valve might be inconsistent and failing to re-equalize the vacuum on the pedal side of the diaphragm, but like you say, would that be enough to stop the proper rod return.   I guess a faulty spring in the servo could cause this too, or in the master cylinder...  but why would it be binding more on one side?

 

Regarding the gradual build up of brake drag as they bind.  Is this due to the binding causing heat, which then heats the components and fluid causing further binding, causing further heat until they start to smoke?  Or does this suggest a gradual process (leak?) somewhere that gradual increases the pressure in the calliper which is only reset when I come to a stop and apply full pressure to the brake pedal?

@DaveSk I think if you have a look, you'll see that the surfaces I'm referring to aren't part of the caliper.

 

Item 7 here, the horizontal surfaces on the left of the bearing housing in the diagram.

Edited 18 March, 20188 yr by Wino

When you run in a new car you are running in new brake parts that are close and un-worn, and get hot.

 

When you have overheating brakes on used cars it is usually because of the pads not getting thrown back and too close to the discs.

Rusty sliders, calipers as is being experienced.

So when all else is working or even not, you still need to know the brakes move back from the discs.

 

The car stood for 6 months, and it is a 2010, 

are you sure the calipers are the OEM ones and the pads are correct?

Another thing is, is it the original discs still on the car?

(Just interested the car is as was from the factory, never any front end damage so repairs or just upgrades even.)

 

?

Is it the standard wheels that are fitted?

Edited 18 March, 20188 yr by AwaoffSki

Presumably if you had new callipers then the guide pins were also replaced?

41 minutes ago, AwaoffSki said:

When you run in a new car you are running in new brake parts that are close and un-worn, and get hot.

 

When you have overheating brakes on used cars it is usually because of the pads not getting thrown back and too close to the discs.

Rusty sliders, calipers as is being experienced.

So when all else is working or even not, you still need to know the brakes move back from the discs.

 

The car stood for 6 months, and it is a 2010, 

are you sure the calipers are the OEM ones and the pads are correct?

Another thing is, is it the original discs still on the car?

(Just interested the car is as was from the factory, never any front end damage so repairs or just upgrades even.)

 

?

Is it the standard wheels that are fitted?

The callipers and hoses are OEM.  

I can only hope that the pads are correct.  One thing I noticed on other FSIII guides is that it mentions that there's a specific piston side pad.  I'll check that and the pads ID.

Discs.... I don't know.  I have noticed that the passenger side disc is perfectly smooth whilst the drivers side has undulations if you run your finger from the middle to the edge, but no distinct scratches.  I'll compare the lip and the edge of them both.  

Standard wheels as far as I know. 

 

Interesting question....   yes it has had front end damage.  

It was described as "a bump in a car park".  There is a scuff mark on the bumper, along from the number plate near the passenger side headlight, and a small crack to the plastic skirt below this on the thinner part of the bumper beneath the bottom grille.  If you look at the car from the front the gap between the bonnet and the top of the headlight is slightly wider on the passenger side, and I've noticed a small patch of respray overspray that suggests that the passenger side front wing panel has been replaced.  

Cheers

45 minutes ago, amwphotos said:

Presumably if you had new callipers then the guide pins were also replaced?

I'll ask.  I can only hope so.