Weird Brake Problem!!

I can't answer that wasn't there to see it. How did you bleed the brakes and how did the garage. If pressure bleeding must NEVER EXCEED 1 BAR pressure.
What has the garage said to you? It is possible that a faulty unit has been fitted. You have to be a bit more careful with the A2. As said I either use a good self bleed kt or at most vacuum the fluid through and not use pressure bleeders as difficult to make sure the pressure is not too high. Also the use of the block of wood to prevent the pedal going to the floor.
I have known several attempts to thoroughly bleed the brakes especially if a line was replaced or the incorrect bleeding sequence used. Also bet the garage never bled the clutch.
 
I used a sealey bleeder and set the pressure to 14psi. I can't say how the garage did it other than using a 'power bleeder' I asked if he'd bled the clutch and the garage argued that they didn't need to.
 
My worry now is that the master cylinder for RHD vehicles is NLA from autodoc (I must've had one of the last ones). Please can anyone recommend another source or say if the LHD one can be used at all.
 
I doubt the LHD ones are interchangeable with our RHD. If I remember the LHD also has a larger diameter brake servo, so again that could also possibly change the mounting point size. Do you still have your original master cylinder? If so you MAY find that it could either be taken apart by yourself or perhaps rebuilt by a specialist.

I have found a repair kit on ebay, but you would need to carefully check applicability to your master cylinder....


www.ebay.co.uk

For AUDI A2 Brake Master Cylinder Rebuild Repair Kit (M1744) | eBay

A2 1200 TDi 2001 2005 ATE 22.20mm. A2 1400 2000 2005 ATE 22.20mm. A2 1400 TDi 2000 2005 ATE 22.20mm. A2 1600 FSi 2002 2005 ATE 22.20mm. Brake Caliper Pistons. Brake Caliper Repair Kits. Our dedicated and knowledgeable staff have many years of motor industry experience to help advise you through...
www.ebay.co.uk
 
Right, so a bit more fault finding....
The 2x M12 port on the master cylinder were plugged with the reservoir full.... The pedal is firm and feels good.

I now suspect the valve block on the ABS unit is passing fluid. I found a YouTube video of a Volvo owner (fitted with same ATE Teves Mk60), who has the same issue. Had diagnosed it as a bad master cylinder to find that the fault still existed.

I have found a good second hand valve block and pump which I will swap out and see if the fixes the issue.

Watch this space
 
So.... Finally it has been fixed!
It was a leaky valve in the ABS valve block.

The lessons learned here are to diagnose the master cylinder by blocking the ports on your master cylinder and see if a good pedal feel can be achieved when it's full of fluid but the service ports capped.

Secondly I found a second hand ABS pump. The ECU on the ABS unit is coded to my car, to avoid extra pains I swapped the ABS ECU over. My car now has its original ABS ECU sitting on top of a good second hand ABS valve block and it works a treat now
 
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