Brake Master Cylinder - major failure

[MARLBORO_LITE 0]

Help needed! Apart from the dealers, any suggestions where I can buy a new brake master cylinder for a 93K Corrado 2.0 16v WITH ABS? If I didn't have ABS this is a far less problematic quest apparently!!

 

I enjoyed a major failure exiting the M4, only found out I had no brakes as I attempted to slow down to join a large roundabout! I have bent the handbrake, broken the plastic trim around the handbrake, got teethmarks in the steering wheel and turned the drivers seat subtle autumn shades of beige and brown!!

 

I take it that it is the master cylinder though: symptoms being no pressure on the pedal, depresses fully to the floor, slowly returns? I'd appreciate some views please. As I drove the car home (in 2nd, with handbrake in hand!) I either had no brakes at all or the freeking bite would put me through the windscreen!!

 

Dealer price for the article concerned is £187 +VAT.

 

My name isn't in that white bearded bloke's book it would seem!!

[boost monkey 0]

You sure it's the cylinder and not the servo?

 

And would you accept a 2nd hand one? I've got one coming on my parts car at the weekend, not sure the condition of it yet though

 

hth,

 

Jon.

[G60SC_Stoney 0]

have you tried gsf? just make sure you get a good quality one! as im sure you have realised-safety is paramount!

[boost monkey 0]

I take it that it is the master cylinder though: symptoms being no pressure on the pedal, depresses fully to the floor, slowly returns? I'd appreciate some views please.

 

The servo mech (that's the big disc behind the cylinder) has a spring in it, and i think this is what pushes the pedal back up after you take your foot off, will offer it up to the powers that be though.

 

My spare does come from an ABS car and I don't have ABS so don't have a problem with parting with it. As mentioned, will check condition and get some pics up.

[Supercharged 2]

I really would get a dealer one - thats the only place i could find to sell me a proper ATE one that are now alloy rather than cast despite Eurocarparts being an ATE dealer...

 

I wouldn't trust a second hand one now these caras are 10 years old minimum!

[boost monkey 0]

Horses for courses.

 

If it has integrity, it will be fine. I'm not saying sling any old part on there.

 

Otherwise, source one from a newer car and then adjust the pedal to compensate?

[MARLBORO_LITE 0]

Cheers fellas (apologies if any of you fellas are galls!)

 

The mechanic I have discussed this with 'thinks' it is the master cylinder. You see as you depress the brake pedal it just feels like the system isn't pressurising (no backwards thrust felt through the pedal). When the car is stationary, I can't get the system to pressurise by pumping the brakes, although when in motion (as I mention below) there was either nothing or by merely brushing the pedal with with a goose feather the car was stopping on a sixpence! Would a defective servo cause similar results?

 

The ironic thing here is that at the moment by ABS system is out. It hasn't worked for about 3 months. I am putting this down to it being a faulty sensor. I hadn't considered this before, but could the defective ABS system cause the total failure I have experienced?

 

I take all the points on board re safety. The ideal solution is a new one but at the moment I aint got those funds lying around. I got my Sorento in for a service/clutch/cambelt so won't see much change from a grand!! GSF couldn't help. I called around the Cardiff branch on a promise that they had one for £50. As I was about to hand over my debit card the lad who was serving me thankfully realised the part was designed for non-ABS systems.

 

What interests me here is, with the shared parts bin that is VW/Audi/Skoda/Seat, are Corrado owners enjoying a penalty for driving a relatively old/rare car when it comes to id-ing replacement parts? I am sure manufacturers don't develop master cylinders specific to particular models. They'll produce something that they can employ across the range of models for efficiency/economies of scale purposes. If someone could give me the parts number I'll phone around a few dealers and see what results I get. Might be an interesting experience. I am pretty sure Seat were in VAG ownership in 1993, not too sure about Skoda though.

 

Boostmonkey - I'll be interested in your used ABS master cylinder providing it looks ok. What age/mileage car is she off?

 

Thanks all once again

[boost monkey 0]

 

The ironic thing here is that at the moment by ABS system is out. It hasn't worked for about 3 months. I am putting this down to it being a faulty sensor. I hadn't considered this before, but could the defective ABS system cause the total failure I have experienced? If your ABS is out, doesn't the big yellow light come on at the dash? Also, there's a sensor a each wheel I think, so are all 4 sensors dead?

 

What interests me here is, with the shared parts bin that is VW/Audi/Skoda/Seat, are Corrado owners enjoying a penalty for driving a relatively old/rare car when it comes to id-ing replacement parts? I am sure manufacturers don't develop master cylinders specific to particular models. Yeah imho, there's a little too much Mark3 build quality in the corrado for my liking, missing my golf at the mo! They'll produce something that they can employ across the range of models for efficiency/economies of scale purposes. If someone could give me the parts number I'll phone around a few dealers and see what results I get. Might be an interesting experience. I am pretty sure Seat were in VAG ownership in 1993, not too sure about Skoda though. There will definitely definitely be other cylinders you can try or will fit, as I mentioned earlier. Some will be bigger and therefore you will get less pedal travel when you put your foot down as you're pushing more brake fluid at any given time.

 

Boostmonkey - I'll be interested in your used ABS master cylinder providing it looks ok. What age/mileage car is she off?

It's off a K reg, not too sure of the mileage but will check.

 

Thanks all once again

[MARLBORO_LITE 0]

Aye mate, that big orange light has been out for quite a while now. I had front near side sensor replaced Nov last year, need to check the others is my guess. Please keep me in touch on the used MC. I may do a temporary fix for now till I can identify a new reasonably priced one.

 

Anyone got the part number for the MC with ABS (2.0 16v K plate)?

 

Anyone replaced their standard MC with a cheaper but just as effective new item?

[MARLBORO_LITE 0]

Correction - big orange light has been permanently on not out!

[boost monkey 0]

Please keep me in touch on the used MC.

 

Anyone got the part number for the MC with ABS (2.0 16v K plate)?

 

Yeah no probs.

 

Vagcat is telling me your MC is 358 611 019 D. Looks like it has 2 extra pipes coming off and going to the ABS unit?

[Supercharged 2]

The 2 extra pipes go from the fluid res dude.

[boost monkey 0]

Aha, thanks.

 

Not a huge fan of the Vagcat exploded diagrams! :lol:

[MARLBORO_LITE 0]

Thanks to boostmonkey for supplying the ABS brake master cylinder, I began the job of fitting it half an hour ago but didn't take it very far. Update:

 

Switch ignition on, engine starts (glad something is going my way!), ABS light stays on (as it has done since Nov last year!), brake pedal pressure seems normal (no pedal gliding effortlessly to the floor!). Then, as I am sat behind the wheel contemplating life over a quick roll-up, I hear a strange (sort of cross between a) groaning & buzzing sound, which, after investigation, appears to come from the ABS pump! So, now I am wondering whether a defective ABS pump could be the problem? When the pump is making this noise the brake pedal pressure is solid (only got to touch it slightly and it's pushing back at me).

 

Help please guys and gals. This is getting me stumped! Would a VAG COM investigation tell me what is wrong?

 

Boost monkey - you looking to sell an ABS pump and ECU if not required :lol: ?

[boost monkey 0]

Alright matey, glad you got the MC fast but a bit gutted it might not solve your problems! :(

 

IIRC, the ABS light stays on when one or more of the sensors is malfunctioning? Might be worth popping your car up at some point and checking all 4 corners for each sensor.

 

Don't think the car came with ABS ECU, but if someone knows what it looks like I will have a root around. Similarly on the ABS pump, although if we have it will have to check that it hasn't been bagsied by a family emmber already!

[Supercharged 2]

ABS ECU is in the passenger kick panel in front of the door...

 

I would check the existing one for water damage but I would say if the pedal sank to the floor before the problem must have been hydraulic regardless of ABS - if there is another issue with the ABS you need VAGCOM...

 

Edit - I'm sure you need VAGCOM anyway if changing the MC as this will involve bleeding the ABS unit...

[MARLBORO_LITE 0]

Cheers Supercharged - defo hydraulic......initially. It's as if the ABS system is in a state of permanent alertness, the noise it is making I am sure is the noise I have heard once or twice from the pump when I was locking up under braking.

 

Cheers Boost monkey - if you want to part with the ABS ECU please let me know. I am on the trail of a low milage ABS pump from a Golf GTi MkIII. I just posted a plea for assistance asking whether t'll fit my C.

 

Need to book her in to a garage methinks, DIY no longer an option. I think I'll get the AA out tomorrow, maybe they have some diagnostic VAG COM equivalent goodies on board their yellow vans. They'll have to tow me to a garage anyway!!

[Supercharged 2]

I'd do a few checks first mate like whether all the sensors have continuity and that the ABS ECU isn't full of water...

[MARLBORO_LITE 0]

Will do Supercharged, have Saturday free!! I'll inspect ECU and visually inspect ABS sensors. I don't have VAG COM though so can oly give 'em a good clean and make sure they are properly positioned. When you say sensors having continuity, what does that mean exactly (I write letters for a living and keep politicians out of jail!!)?

 

Cheers

[boost monkey 0]

there's a setting on good multimeters called continuity.

 

This basically makes a beeping or buzzing sound when the two probes have a clear electrical path between them.

 

For example, you will get continuity if you touch the battery - terminal and the earth lead, or anywhere on the chassis (within reason!)

[MARLBORO_LITE 0]

Well, just in case anyone else experiences the same symtoms as I, I thought I'd share with you all the fix!

 

After doing a fair bit of reading on the forum and other sites, I bought an ABS ECU (from r4-ge - thanks mate) and replaced mine with that. It was obvious when removing the old ECU that at some point water had gotten into it. There was rust at the bottom edge and when I removed the terminal block I could see that the female terminals in the block connector had suffered from water ingress and there was a thick milky gunk around the male terminals on the ECU unit. I dished the old ABS unit, cleaned up the terminals in the connector block using a mini wire wool brush (looks a bit like a tooth brush - perfect for the job), then attached that to the new unit, and hey presto, eveything working perfectly. Proper pressure on the pedal, ABS light now goes off after 3 odd seconds. Well happy. :clap:

[boost monkey 0]

Goods news matey!

 

Glad you got it all sorted :D

[MARLBORO_LITE 0]

Aye indeed, and thanks to you for the master cylinder. I aint fitted it yet, the strange things happening with the ABS pump made me think it wasn't the MC afterall. I'll probably hold on to it though, always a good spare to have in the bottom drawer!!

 

Right, what's going to go wrong with her next!!?? :shrug: