# Brake pedal soft and sinks to the floor



## pnmrr (Jun 3, 2012)

I have been dealing with a never ending problem with the brakes on my 1991 Jetta to the point where it has forced me to seek outside help. 

I have read this and other VW forums over the years and have enjoyed reading all the tips and ideas that are generated on these sites, but it is not very often that I post on them, I just like to lurk. I am asking for any ideas or past experiences that some of you may have had that is similar to mine and may be able to help. 

The brakes on my car have never really been all that special ever sense I owned it, even after I changed the master cylinder, calipers, rotors, wheel cylinders and front rotors about 2 years ago. They did the job and stopped the car, for the most part, I just down shifted a lot and lived with them. 

Recently I have been considering selling the car and decided to fix the brakes once and for all. I noticed that when I applied the brakes hard, it would slowly sink to the floor. Great, a bad master cylinder, swapped in a new one and the exact same problem occurred. After playing with it for awhile, and bleeding the heck out of it, nothing changed, so I swapped the master out, again. 

After several quarts of brake fluid flushed through it with a pressure bleeder and the good old fashion 2 person pump the brake pedal method, the same thing. It never really ever feels like it pumps up due to air in the system, the pedal just goes about halfway down before it starts to feel like it is doing something and then slowly goes to the floor. 

I finally decided to cap off all the lines at the master and see if it was the problem or something down line. Once capped, the master felt hard and did not go to the floor. As I added the front left, it felt a little less firm, but pretty good over all. I then added the right front and if felt much softer. So that was it , I replaced the front calipers and hooked up the rear brakes, bleed them to death again, and the brakes are exactly the same, right to the floor. 

This happens mostly with the engine running. With the engine off, they seem to hold up a little better, but with enough effort, they eventually hit the floor. I have changed the lines from the master cylinder back to the portioning valve and all other lines are dry and clean, no leaks noted at the wheel cylinders or anywhere else for that matter. The fluid level does not go down either. 

I am really at my wits end, I have tried everything I know and don’t have a idea of what to do next. I have worked on cars for many years, and brakes were never considered to be that big of a problem, but this one sure has changed that. Any suggestions or advice would be greatly appreciated. 

I realize this turned into a long post, but I wanted to get all the info out there.


----------



## i4turbo (Oct 26, 2006)

I have the EXACT same problem 

I hope someone knows wtf is going on 

THANKS


----------



## germancarnut51 (Mar 23, 2008)

Are the parking brakes in working condition, and do you use them? 

Are the rear brakes in good working condition, and properly adjusted? 

Are the "new" master cylinders you say you installed really new or used ones you got from the junk yard? What brand are they?


----------



## pnmrr (Jun 3, 2012)

Brakes and all related componets were replaced when I started drivng the car. Sense then, while trobleshooting this problem, the rear wheel cylinders have been replaced and the brakes adjusted per the bently manual. New ( rebuilt) calipers in the front and new (rebuilt) master cylinders from Advance Auto, I know not the best of sourses, but, its just a master cylinder, surely they couldn't screw up 3 in a row! The brand escapes me, was not really paying attention.


----------



## Elwood (Aug 10, 2001)

Do you have ABS? I don't remember when that was introduced.

Edit: OK, it looks like you do have ABS. If you don't cycle the pump while bleeding, you'll never get the air out of it.


----------



## pnmrr (Jun 3, 2012)

No ABS, Simple, dumb car, that's why I liked it. To tell you the truth, this whole thing is just short of getting stripped and dumped in the bone yard, I am getting fed up with this thing.


----------



## Elwood (Aug 10, 2001)

I understand your frustration. My only recommendation would be to buy a new VW MC and give it a go.


----------

