Spongy brakes on new Beetle

Hi guys,

Having problem with 2001 Beetle. Have just replaced all brake pads and front discs and replaced brake fluid. Noticed brakes were really spongy so bled fluid and replaced again but still have same problem. Is this likely to be air in master cylinder? Pretty sure there is no air in rest of system having repeated bleed

With ignition off brake pedal is solid, but as soon as engine is started, pedal becomes very spongy.

Any suggestions on how to remedy this? Is it possible to bleed master cylinder? Noticed there are 2 bleed valves on top of cylinder so can this be done without removing from car?

Reply to
Stevo
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Is it any worse-spongy or the same-as-before-spongy? VW brakes IMHO are usually softer and with more travel than most cars. It could be just how they are.

that's typical of any power-assist brake system due to the lack of engine vacuum for boost when the engine isn't running.

Reply to
Matt B.

Reply to
Stevo

well it could be air in the M/C, yes, if you let it get too low during the first bleed, but yeah the repeat bleeds should fix that.

However did you use a vacuum bleeder or a pressure bleeder or did you just bleed it w/the brake pedal? If you did the brake pedal and you pushed the pedal more than just the usual length of travel, you may have destroyed the inner M/C seals. Even when bleeding you shouldn't overrun the normal pedal travel range or the seals can get damaged and as a result it might be leaking internally. In other words, fluid isn't leaking out, but it's leaking past the piston such that you aren't really compressing just the fluid anymore...you're just "squeezing" the fluid around inside the cylinder from one part to another. If this is the case, it's new M/C time.

Reply to
Matt B.

Sounds like an $800.00 trip to the dealer. Did you use "official" VW brake fluid?

Reply to
Carlton

Is that the stuff that comes in the Czech cut-crystal decanters with the certificate of vintage?

Bill Longyard

Reply to
William Longyard

Some have suggested that pressure bleeding works better than the old fashion pump and open bleed screws I grew up doing. If the master cylinder has some issues like rust you may have goofed up the seals and the master cylinder is leaking internally. If your Beetle is similar to my 2003 Jetta there should not be any mushyness or significant travel.

No, driv>Pedal is definitely lighter than before having to press almost to the

Reply to
Jim Behning

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