How to get rid of the 'spongy' brakes ?

[5teve L]

I've done a search on here & on the net, but I can't find a definitive answer...
Since owning my car (99 S3) the brakes have never felt right, the pedal isn't stiff like other cars I've driven, it almost feels like it travels to far & is a bit spongy, the brakes seem to work fine though which I find annoying, lol.
Last night I changed the brake discs & the front lines to braided ones which has made squat difference to the pedal feel TBH.
Am I missing something to get a firmer feel or is it something the S3 is known for ??

Cheers
Steve

ps where is the bleed nipple on the MC ?

 

[Matt82]

brake fluid. put some new stuff in there

a pressure bleeder makes it a doddle and the MC nipples are on the nearside of the MC.

is there a nipple on your slave cylinder?

 

[5teve L]

Thanks for the reply, not sure about the slave cylinder, where is it located on the S3 ?
& I have added new 5.1 fluid, the old stuff that came out was black !!
Maybe a full system bleed will help, hence asking where the MC nipple is
I hope I don't have to take it to Audi to get it bled on Vag-com

 

[<tuffty/>]

DOT 5.1 fluid is more compressable than DOT 4, the pedal feel on S3's (and A3's) is fairly soft as std as they are heavily assisted.

You should do a full system bleed every 2 years regardless of mileage, Motul RBF600 or 660 fluid would be my preference to 5.1 stuff as its performance and specs exceeds most DOT 5.1 with none of the downsides of 5.1

Bleeding on VAGCOM isn't really required unless you have replaced the ABS unit or localised brake pipes... the ABS unit is a passive device until required anyway so fluid will flow through easily.

Pressure bleed as suggested using something like the Gunsons EEZI Bleed and no more than 20psi...

<tuffty/>

 

[Matt82]

well i have run a system dry before and pressure bled, the abs was fine and the MC did need to be bled and all was well after that (i did eventually work that out at about 1am haha)

 

[fran-s3]

I had mine done at VW last week and is much firmer.... Just used their OEM VW stuff...

 

[Matt82]

about £50?

 

[1animal1]

how much does the S3 take...just priced this Motul RBF600 up @ £10 a bottle from Camskill........

 

[<tuffty/>]

how much does the S3 take...just priced this Motul RBF600 up @ £10 a bottle from Camskill........

I would get 3 500ml bottles to be sure... done most cars with just 2 though, extra bottle is convenient if you haven't got a bloke just a few miles away with it in stock ;P

<tuffty/>

 

[5teve L]

Thanks I will bleed the system later in the week & see if it improves pedal feel at all. Like I say they work, just feels a bit odd pushing the pedal to the floor near enough. It's almost 2 stage lol

 

[badger5]

air.. OR, worst case if the brak epedal has been pushed to the floor to bleed the brakes, the master cylinder seal may now be damaged... and you will never get a firm pedal again.
hopefully for you its just air.

pressure bleed.

 

[Matt82]

wow, to the floor is impressive! gotta be the master cyl that you need to bleed

id do the first and then test the pedal. hopefully that fixes it. does the funny slave cyl on the s3 have the ability to be bled?

 

[5teve L]

wow, to the floor is impressive! gotta be the master cyl that you need to bleed

id do the first and then test the pedal. hopefully that fixes it. does the funny slave cyl on the s3 have the ability to be bled?

I think there is a bleed nipple yes, I will investigate further, I really hope it's just air & crap fluid but I fear the worse

 

[666markyboy]

Keep us posted as i'm doing mine on the TQS this week.... whats the order for bleeding ? and did i also read somewhere you need to bleed the clutch at the same time as it uses the same fluid or is that the slave cylinder your talking about ???