fla 9 Posted June 19, 2012 I recently converted to 288s which have been great so far. Yesterday however, i had to really press the pedal hard and even then the braking was poor, so i ended up using the gears to slow down as well. A bit scary, i must admit. I thought that if there was air in the system it would make the brake pedal just drop to the floor (or thereabouts), so i assume thats not the issue? It still brakes in a straight line and there is no scratching or grooving of the discs. I will bleed the front brakes this evening hopefully to see if it helps. Otherwise, any suggestions? Quote Share this post Link to post Share on other sites
VW_OwneR_85 2 Posted June 19, 2012 may or may not be your problem but idd give the pads a chance to wear in, { as in wear flat to the disc} , when i upgraded to mk4 rear calipers my brakes were shocking!! so bad that that i bled the brakes like 4 times! it realy was just a case of letting them wear in, Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted June 19, 2012 Brake fade? Quote Share this post Link to post Share on other sites
fla 9 Posted June 19, 2012 Thanks. Pads are new - they've only been on for around 300 miles so far. The surface rust cleans up nicely (car isnt used as much as i would like :( ) but yesterday was really bizarre. Would it be sufficient to bleed just thefronts or should i do the whole system plus clutch again? In fact is bleeding even a possible solution? Quote Share this post Link to post Share on other sites
Roger Blassberg 0 Posted June 19, 2012 Hasan, If the pedal travel is not abnormally long and you are confident that the pads and discs are in order, it would point to a failure of the brake servo or the vacuum supply to it. Best wishes RB Quote Share this post Link to post Share on other sites
fla 9 Posted June 19, 2012 thanks roger. Will have a look later today, although i'm not quite sure what to look for... Quote Share this post Link to post Share on other sites
VR6Pete 0 Posted June 19, 2012 Assume you've checked the condition of the brake line flexi's to make sure they aint buldging or anything under load etc.. ? Quote Share this post Link to post Share on other sites
nino 0 Posted June 19, 2012 ive recently changed front and rear discs and pads and also rear calipers and my brakes feel spongy too, i was told it would get better once they bed in. does make it interesting when approcahing traffic lights! does this sound about right? Quote Share this post Link to post Share on other sites
fla 9 Posted June 19, 2012 Assume you've checked the condition of the brake line flexi's to make sure they aint buldging or anything under load etc.. ? I've replaced them with new as part of the swop but i'll have a check again, just in case they're faulty. Quote Share this post Link to post Share on other sites
daleyboy 0 Posted June 20, 2012 It does sound like a servo/vacuum pipe related problem, i once had a mk1 golf with no servo and my backside would leave the seat when attempting to stop, it had a rock hard pedal and very little braking force. Quote Share this post Link to post Share on other sites
Roger Blassberg 0 Posted June 20, 2012 Hasan, I suggest that you disconnect the servo vacuum pipe at the inlet manifold end (and block the manifold connection, otherwise you will have a massive airleak and the engine won't run !!) then drive it - slowly - down your quiet road and see if it makes any difference to the brakes. If it does NOT then you clearly have a servo problem. I would imagine that the diaphragm could have developed a leak in which case it won't be helping the pedal pressure, or maybe there is a blocked airway somewhere internally. Alternatively there may be a blockage in the vacuum pipe itself; disconnect it at both ends and blow through it to check. The rigid plastic pipe that runs over the coilpack area is connected to the inlet manifold with a piece of rubber hose (which on mine looks a bit second-hand these days!) Perhaps that has collapsed internally. Best wishes Roger Quote Share this post Link to post Share on other sites
buttles 0 Posted June 22, 2012 Easier, say safer way to check servo is to pump brakes with engine off a few times to exhaust any vacuum. Then press pedal and start engine. As vacuum builds the pedal will go down. If it doesn't then servo is not working somewhere. Ignore kick of ABS system priming. Neil Quote Share this post Link to post Share on other sites
fla 9 Posted June 22, 2012 i'll try that Neil, thanks. Quote Share this post Link to post Share on other sites
fla 9 Posted June 23, 2012 Easier, say safer way to check servo is to pump brakes with engine off a few times to exhaust any vacuum. Then press pedal and start engine. As vacuum builds the pedal will go down. If it doesn't then servo is not working somewhere. Ignore kick of ABS system priming. Neil OK tried this and it seems to check out ok. I'll jack it up tomorrow and spin the front wheels and get someone to apply the brakes to see if there's any binding or seizure of the caliper pistons, although it doesnt pull either way. Strangely, i reversed earlier today and slammed on the brake to test it, and it pulled it up pretty sharpish. Confusing. Quote Share this post Link to post Share on other sites
fla 9 Posted July 19, 2012 as above the rear brakes work better in reverse than the 288s work going forwards!! Is it feasible to just bleed the fronts and ABS unit without doing the rears? Quote Share this post Link to post Share on other sites
daleyboy 0 Posted July 19, 2012 You could try, as it wont be a lot of fluid, but if there is any in the abs pump it will find its way into the rears as well. I would also have a check of the pipe between reservoir and abs pump (little rubber grommets) as thats where mine is leaking Quote Share this post Link to post Share on other sites
