Flushing brake system, bleeding master cylinder and ABS pump (w/ ESP)

[YzRacer212]

Thanks for the writeup! I tackled this job myself yesterday and today and ran into a little trouble when my pressure bleeder pushed an air bubble through. I ended up using a combination of the pressure bleeder (with 29psi) and cycling though the test in VCDS. It took over a quart of fluid to get all the bubbles out, some of them were very deep in the system so I had to let a lot of fluid purge before I saw the bubbles. The ABS light remained on but I had a solid pedal so I took it for a drive and the light went out, everything is working fine now! I had tried using the ABS basic settings to set off the pump, but that didn't work, I ended up going through the output test where you press and release the pedal and it checks each wheel. Moral of the story it to take your time, avoid air bubbles, and if you get one be patient while purging them out.

[Timwa Tumble]

do you need to login to do this basic setting. if so is it the login for the car or the one you use for doing the steering wheel set up?

[YzRacer212]

Originally Posted by Timwa Tumble

do you need to login to do this basic setting. if so is it the login for the car or the one you use for doing the steering wheel set up?

I did not have to login, but the basic setting did not work for me. I went through the output test step by step while it actuated the pump and all the valves.

[Timwa Tumble]

basic setting did not work for me either. how do you do the output test?

[YzRacer212]

Originally Posted by Redneck Truck

When I disassembled my right rear caliper I lost a lot of fluid and I think air got into the master from the top. After a lot of bleeding with a pressure bleeder and by hand, but I've still got a spongy pedal. I'm aware of how to use VAG COM basic settings to bleed the ABS pump, but I'm not aware of any special procedures for the ESP, and I don't know how to bleed the master cylinder. Could anybody make/find me a brief writeup on the job?

Just make sure your pressure bleeder is full, and I also went to the effort of getting all the air out of the pressure bleeder tube, so that only fluid would be going into the master cylinder. I used up to 29 psi and up to 2 quarts of fluid.

[dcaron9999]

Originally Posted by YzRacer212

Just make sure your pressure bleeder is full, and I also went to the effort of getting all the air out of the pressure bleeder tube, so that only fluid would be going into the master cylinder. I used up to 29 psi and up to 2 quarts of fluid.

How did you prevent air from going through your power bleeder tube - did you fill the tank with fluid, then fill the tube itself? How did you manage to then screw the bleeder lid top the fluid reservoir without spilling?

Im up to my third brake bleed, and two bedding sessions. I still have a soft pedal, with too much travel. No leaks anywhere. Brand new pads and rotors.

[jcman]

Originally Posted by dcaron9999

How did you prevent air from going through your power bleeder tube - did you fill the tank with fluid, then fill the tube itself? How did you manage to then screw the bleeder lid top the fluid reservoir without spilling?

Im up to my third brake bleed, and two bedding sessions. I still have a soft pedal, with too much travel. No leaks anywhere. Brand new pads and rotors.

Time warp questions from May of 2012 get very few replies

[YzRacer212]

Originally Posted by dcaron9999

How did you prevent air from going through your power bleeder tube - did you fill the tank with fluid, then fill the tube itself? How did you manage to then screw the bleeder lid top the fluid reservoir without spilling?

Im up to my third brake bleed, and two bedding sessions. I still have a soft pedal, with too much travel. No leaks anywhere. Brand new pads and rotors.

It has been a while since I have been on here, and a while since I did the job! If I recall correctly, I was able to mostly fill the reservoir, then connect the power bleeder. I believe I was somehow able to apply a little pressure, and release a couple of times. When new fluid flows into the reservoir, I was able to get the air to come up the power bleeder tube. Eventually I would have the air bubbles all locate far upstream on the tube or even all gone into the bleeder tank. Once that was squared away, I could apply some good pressure with no fear of inducing any air into the system.

Any air induced into the system can be difficult to remove, as well as frustrating. It took me almost 2 quarts to get the air out, probably because I didn't take my time to start with.

[dcaron9999]

Originally Posted by YzRacer212

It has been a while since I have been on here, and a while since I did the job! If I recall correctly, I was able to mostly fill the reservoir, then connect the power bleeder. I believe I was somehow able to apply a little pressure, and release a couple of times. When new fluid flows into the reservoir, I was able to get the air to come up the power bleeder tube. Eventually I would have the air bubbles all locate far upstream on the tube or even all gone into the bleeder tank. Once that was squared away, I could apply some good pressure with no fear of inducing any air into the system.

Any air induced into the system can be difficult to remove, as well as frustrating. It took me almost 2 quarts to get the air out, probably because I didn't take my time to start with.

Nice technique. Will definitely give this a try next time.

I think I actually solved my problem. The brake booster pushrod (sitting behind the brake pedal) needed a little adjustment, to allow it to exert longer stroke into brake booster. My allroad now stops after 1.5 inch pedal travel and what seems like less pedal effort.