2005 Jetta ABS bleeding help request

I have a 2005 Jetta 2.5L Value Edition, 5Spd that has a brake problem. I just bought this car, knowing it had a brake problem that I thought was a master cylinder issue. The symptom was that the brake pedal was going to the floor with basi cally no resistance, but was still providing some braking ability at the end of the pedal travel, just not very much. I have replaced the master cylinder, but in removing it I noticed that it was quite difficult to separate it from the brake booster, and I mean beyond the normal initial breaking of the seal between two devices that were bolted together for an extended period of time. This was an unusual grip I had to break. After removal of both devices I realized that the push rod in the brake booster had been stuck inside the plunger assembly of the master cylinder - definitely NOT normal. That push rod broke off in the separation process thus I replaced the brake booster. Once I replaced both items and refilled the master cylinder I realized that the rear brakes weren't bleeding as I would expect them to (I was doing that with an assistant, (although I do have a Motive Power Bleeder) and when I did some online research I realized that there was a need to do an ABS system bleed first, which is done with the VCDS, which I do have.
I also note and find quite curious, that every time I re-attach the battery that the brake lights go on and stay on until I disconnect the battery.
I'm assuming this is because the whole breaking system hasn't been completely reset yet.
I have prepped both front wheels for the ABS bleeding process.
Now, to the VCDS process -
- the procedure I have seen directs the user to go into Select Control Module / 03 ABS Brakes / Basic Settings - 04 (Advanced Functions area) / then ABS option, then make sure the Group is set to 01 and select 'Go' and that the VCDS will direct you step by step from there.
When I follow that, the 3 cells just to the right of the 'Go' button are showing, "Press pedal", 'and', & 'hold' and they never go away, no matter how long I hold the brake pedal down - and keep in mind that there's basically little to no resistance when I press the brake pedal, unless I pump it repeatedly which generates some resistance, but not for long. I'm suspecting that I'm either missing something basic or that perhaps the ABS unit itself is messed up?
I think I've provided enough details, but if not then please ask away and I will do my best to answer whatever is asked. And thanks, in advance for any help!

The brake system and hydraulic clutch use the same reservoir and fluid, and are thus very interconnected. Accessing the bleed valve for the clutch requires removing some of the intake plumbing, etc. This may have something to do with any problems you are having. It also may not.

sptsailing said:

The brake system and hydraulic clutch use the same reservoir and fluid, and are thus very interconnected. Accessing the bleed valve for the clutch requires removing some of the intake plumbing, etc. This may have something to do with any problems you are having. It also may not.

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Thanks for your response sptsailing, though the clutch is working fine, so I'm not sure if there's any issue there?

I tried to use the ABS bleeding function in VCDS today. As for your issue, when you pump the brakes (when it tells you to) you need to press ok after and then it moves to the next step (or maybe this is what I was doing wrong?) from there it will tell you to hold the pedal down while valves are closed and the ABS pump runs. Then the next step asks you to pump again, and then back to hold pedal down and so it repeated this again and again for the 5 times I did it (each time pressing the ok button at the top to proceed) - It never told me to open the valves to bleed fluid so I started getting worried that I was doing something wrong and decided not to bother and just flushed the clutch/brakes. I am not sure if eventually after going through this process many times that it will finally tell you to open the valves to bleed them but it's my impression that when the ABS pump runs, you'd want the valves open so it can actually pump the fluid out, and you're holding down the pedal so it won't let air in the system. But it always said "close position" so I don't know what's up with that. I also had a power bleeder so I don't even see the sense in me pumping the brakes at all. Correct me if I'm wrong but couldn't I just hook up my power bleeder, open the valves and run the ABS pump rather than doing all of this brake pumping?



As for the clutch, yeah you need to take off your air intake pipe (from filter housing to EGR assembly) and I actually just ripped out the whole airbox since I have a lot of extra crap in there/hoses and not a whole lot of access. On top of the differential is 2 ports, one on the right is the bleeder valve. Pop the cap (if there is one) and open it just like you do with brakes and try like crazy not to spill the brake fluid all over your engine components. I found it easiest to just run a long hose from there to under the car with my catch bottle.



I also think my reservoir was leaking a little from the top when I pressurized it. I only went to 10 psi. So I guess next bleed I should replace that thing to be safe. Will it be as simple as drain it and rip it off and replace or is there a whole world of fun to be found under that thing? From what I could tell, it was just a rubber hose coming off the bottom/right side of it.


Probably a good time for me to note that mine is an MK4.