Caliper problem 100 turbo

[TeXerv]

Originally Posted by pimpdriver

http://www.sjmautotechnik.com/troubl...rake.html#bomb

Very helpful picture and a very good explanation! But the "connector not used" is provided for self levelling suspension.
And pressure reservoirs can become overhauled and refilled, as long as the diaphragm isn't blown.
A worn pressure accumulator may also be harmful for the pump and the pressure hoses, because the pressure valve inside the accumulator is working with high frequency. And at each regulation point a shock wave is getting into the pressure system.

[saladdodger]

Originally Posted by missfire

Take it to Audi and get them to bleed it.

Your joking right?

It been done a proper machine dude

[TeXerv]

Originally Posted by saladdodger

Your joking right?

It been done a proper machine dude

My way to check the master cylinder, if I had doubt about it's condition:
Shut off the engine and actuate the brake pedal for a few times until it feels hard.
Then hit the pedal and keep it actuated with highest foot force for minimum one minute.
As the pressure decreases there is a leak. In your case (no external leakage visible) it may be the master cylinder (I suggest) or the anti lock block.
Checking the master cylinder: Disconnect the brake lines from the master cylinder and fit bleeder screws instead of them. Bleed the master cylinder directly via the fitted bleeders.
Now hit the break again and keep it actuated (like before). As the pressure decreases, the master cylinder is faulty.
This is a pretty quick and dirty way to test the master cylinder and it works.

[ovalking]

Originally Posted by saladdodger

The pedal is hard when engine is off but when started its goes to the floor with slight resistance and juddering.

I don't understand what conditions cause this affect (pedal to floor only if engine running). I searched for info but am non the wiser.

I know you're fed up with this, but have you tried running the engine with the hydraulic pump drive belt off?
That way you'll have no servo assistance, but ABS etc. will all be powered up.
Resultant behaviour of pedal might offer a clue.