Weird brake problem

[Error404]

Anyone know is the CQ and S2 (and any other models) share the same servo then?

Will make life easier looking for a resonable replacement

[Error404]

ok, i am going to go the whole hog and replace the bomb with a known good one, and the master cylinder and the servo from a much lower milieage car and see where that gets me

.....and just when I thought I was almost finsihed

[Cullam3n]

might as well do the whole shebang and do the hydraulic pump as well Last time I checked it was £185 + VAT for a recon unit at 4ringspares

[Acidburn]

ok, i am going to go the whole hog and replace the bomb with a known good one, and the master cylinder and the servo from a much lower milieage car and see where that gets me

.....and just when I thought I was almost finsihed

Um.... I'm bringing up a master cylinder unit, abs unit and bomb for you at the weekend if thats any help

[Error404]

err.. i might see how i get on with these bits first.. thats a whole bunch of wonga!!


can anynone with the family album tell me which cars share the CQ master cylinder and servo? I've been offered both but am a bit concerned that they are not right for a CQ

[Acidburn]

I would have thought the one from a saloon 20v and a coupe quattro should be the same as its same setup all round.

[Error404]

nice one Peter

I've found a servo unit too, also off a 90 20v..... does anyone with EKTA know if these are the same part numbers as the CQ?

[Acidburn]

I will try check etka later, but tbh i'd have thought it would be the same as the brakes are the same only difference is with the quattro there is the drivetrain weight but don't think that they upgraded the brakes to compensate for this.

[LHD_Kid]

I show both with part number 893 612 107 A
would wait for another to confirm though, as I never really trust myself with it.....!
Chris

[steverrquattro]

An old thread I know, but what was the cause of this as I am having the same problem?

[A80Avant]

I never found the cause on mine. Exactly the same problem and after 3 bombs and one servo I threw everything away to a vacuum servo with a single vane power steering pump. Problem solved

[Error404]

Servo was bad

[steve briance]

I have a vacuum servo waiting to go on my car when the weather picks up (i'm a driveway mechanic) what single vane pump did you source?
I have read it is possible to disable the brake system side of the twin vane pump by undoing the top cross head plug and removing a plunger (no plunger, no pressure) but i would rather get a single vane pump and do it properly.

I'd heard a pump of a 4.2L A8 works?...

[A80Avant]

I tried that and the pump squealed like a pig. So I ended up with a single vane pump and a modified bracket. I think it was from an audi 100, 100 bar
I can't remember the part number so when I get the chance I'll dig my album out. I may have written in in the special thread of the vacuum servo conversion though

[Error404]

Removing the pistos from the stock pump is the ghetto mod.
This is the proper solution

http://www.s2forum.com/forum/showpost.php?p=808266&postcount=1116