Brake problems!! HELP!!!

[rossgal]

I have serious brake trouble on my 1.9 tdi 2005 B5 estate.

The brake pedal is suddenly travelling halfway down on the initial press of the brakes!

Both front flexi pipes have been replaced along with the master cylinder to no avail. The pedal is solid with the engine off and goes to the floor with it on. This is not the usual creep down found on diesel cars, the pedal can be solid, but if you leave it alone and then apply it again, it goes right down.

It has been bled umpteen times, in a variety of manners.

Does anyone know if there is some sort of vacuum valve?? or pressure relief?? in the system???

I am at my wits end.

It hasn`t been to VW yet, but so called specialists have failed to come up with an answer, and I would rather spend the money to get it fixed, rather than to have someone LOOK at it.

Much appreciation if anyone can help with any clues!!!

Thanks for your time.

[STEWY L]

do you not need electronics to bleed the system correctly ?
i'm sure i have read on this forum that in order to bleed the system correctly
then a laptop/ vagcom is required.
i would try the search facility at the top of the page
"bleed brakes" or similar,
regards,
stewy.

[rossgal]

do you not need electronics to bleed the system correctly ?
i'm sure i have read on this forum that in order to bleed the system correctly
then a laptop/ vagcom is required.
i would try the search facility at the top of the page
"bleed brakes" or similar,
regards,
stewy.

Hi mate,

thanks for the reply, I`ve been through lots of posts on here, I`ve also got a 2003 tdi Passat, and I`ve never had any bother bleeding that, so I`m not doing anything different from that. I`ve never used electronics and had no problems. I am wondering if there is something else in the system that would be causing this as I have no fluid loss, and the pedal is rock solid without the servo assistance.

Cheers.

[martin1810]

You don't need lap tops or electronics to bleed the brakes. You may have a faulty servo although this usually results in harder brake pedal. I would certainly consider changing the master cylinder in case fluid is leaking past the seals and letting the pedal sink.

[rossgal]

You don't need lap tops or electronics to bleed the brakes. You may have a faulty servo although this usually results in harder brake pedal. I would certainly consider changing the master cylinder in case fluid is leaking past the seals and letting the pedal sink.

Already changed the master cylinder, this has had no effect, hence the reason I`m after other suggestions.

Thanks.

[martin1810]

Did you change the servo at the same time as the master cylinder. Servo problems are a well known issue with the passat. They are known to fill with water and cause all sorts of problems.

[rossgal]

Did you change the servo at the same time as the master cylinder. Servo problems are a well known issue with the passat. They are known to fill with water and cause all sorts of problems.

Hi, I haven`t changed the servo, but surely the brakes would be soft when the servo is off?? The servo assistance is working, as when the car is running, that is when the pedal goes down, surely they would be hard if the servo is knackered???

Again, any help/ suggestions appreciated, as I`m at a loss with it!!

Cheers.

[grhdylan]

Are u losing fluid ? .... it could be a faulty clutch. The brakes & clutch use the same fluid, authough i would have thorght u would have had other symptoms with the clutch / gearbox ?

[rossgal]

Are u losing fluid ? .... it could be a faulty clutch. The brakes & clutch use the same fluid, authough i would have thorght u would have had other symptoms with the clutch / gearbox ?

Hi, no fluid loss. Thanks.

[Bookham]

Hi,

I've got a '98 Passat 1.9TDI and have exactly the same problem I think. When driving, on first press of the brakes, brake pedal feels really soft and goes about half way down with practically no braking force. After some rapid pumping braking force is restored but not enough to cause ABS to kick in.

This started immediately after I changed front disk pads. Needed to gently bang the caliper back on one side in order to get new pads in. After painfully slow progress doing this, I remembered to open the bleed nipple. Brake fluid was kept topped up all the way through so definitely no air in system.

Is there a chance I damaged something in the vacuum system?

All help greatly received, guys!