So I just completed installing new SS brake lines, and A8 rotors with TT carriers. The brake install was fine, but the lines gave a little more trouble- I wasn't able to replace the drivers rear side yet because all of the line fasteners were stripped.

Anyhow, now the brakes don't work unless you press them repeatedly and instantaneously. The first time you press them there's no resistance in the pedal and the pedal travels all the way with ease. However, if the car is just rolling it will still stop. But if you immediately press them right after, then they're very firm and the braking is aggressive just as a new set should be. Yet, after a few seconds it just goes back. What could cause this? There's also a little pumping sound, like a 'whoosh' when you depress the brake pedal the first few times. It sounds like the noise a manual air pump makes when you pump it.

I'm thinking and hoping it might have something to do with air in the fluid system. I initially removed all old lines (except the stripped ones) and then bled the system with a motive bleeder. Then the car sat for a few days while I waited for parts- so the system completely drained. Then I installed the new lines and began to bleed it again beginning with the pass side rear. It took about an hour before any fluid came out and another half hour for steady drops of fluid to come.
Once it was dripping constantly I sealed that fastener and did NOT proceed to any other lines because the reservoir was already overfilled and wouldn't take anymore fluid, so I figured it was full. I did however, bleed the master cylinder. I've checked the three ends and they all have fluid pouring through. Don't know about the stripped one tho.

if it helps, the parking brake works well and the clutch is regular too.

 

wait, let me get this straight, you let the system go dry?, didn't bench bleed the master and didn't properly bleed the ABS?

 

yes. (maybe..) yes. and most likely yes.

From the instructions I read for bleeding, I was supposed to bleed at all wheels beginning with the farthest from the reservoir at the pass side rear, and then bleed the master slave as well, all at 15 psi. However, one peronse instructions also stated that if the bleeder empties on the first wheel, then thats it. (so I did not bleed the ABS).

..I let the system go dry while the lines were removed b/c I was painting the brakes, waiting on one set of lines to be shipped and figuring out what I would do with the stripped set(s) I couldn't get off. (so yes it went 'dry').
Then I later connected all lines and used the bleeder to fill the system and bled at all but one wheel. But then the treading on one fastener had disintegrated so the system drained out again over about a day.
I replaced that set with new lines and fasteners and refilled the system, and at this time bled the master cylinder. (I do not know what 'bench bleeding' is so I think its safe to assume that I didn't do it). This last time that I attempted to bleed the system, it took about an hour for the fluid to seap out at the first wheel.

Since it seems that I royally f****d up the procedure, what did I do wrong? and how could I fix it?

The car has not been driven since any of this was done.

 

how and where would I bleed the ABS? and what's a 'bench bleed'? Can all of this be corrected by taking it in to a shop to have the brakes bled? Can I drive it there?

 

my suspicion was right. There was a lot of air in the hydraulic system because i bled the breaks at the wrong place- at the line nipples instead of the calipers. The shop just let the calipers drain a little and then topped up the fluid. All is good now and the breaks are fine. Hopefully I'll get it right in two months when I attempt to tackle that last set of lines as I do my suspension.

 

me and me and me agree! 5 points..Anyone .

Was going to say zeeeee german cars love to trap air in all of the places.