Brake servo assistance - or lack of it

[Felix2566]

Can you keep this thread updated with your progress? Be good to see how its done if I need to do this too. Thanks

[norwichphoto]

Made a start. Ran out of daylight, but inlet manifold almost ready to come off. Found a couple of thin bore vacuum hoses that look a little dodgy, those may have been the cause, but I'll plough on regardless as I only want to do this once.

As I'm waiting for inlet manifold gaskets to arrive, not rushing things.

[norwichphoto]

Well, after a couple of weekends where prior committments have prevented me from getting on, I'm not at the halfway stage. It's an absolute pig of a job! The suction jet pump one way valve has indeed split and seperated.

The vacuum pipe and coolant pipe at the rear of the manifold are really awkward to access.

Had to use a hot air gun to seperate the crank breather pipes where they connect to the turbo inlet pipes, as they were well and truly stuck. I'm going to replace those seals.

[norwichphoto]

Injector seals are currently £ 6.40 each from Audi or £ 0.45 plus postage for pattern parts from Autodoc.
The seals that seal the crank breather pipes into the air intake pipes are 24 x 2.5mm and £ 4.40 each from Audi.

MAF seals are discontinued from Audi/TPS but still available from Audi Tradition

[Felix2566]

Just changed the MAF seals on mine the other day, the new ones really showed how tired the old ones where, surprised they were doing any sealing at all! The bungs in the inlet that the 2 pegs on the bottom of the plenum plug into were missing, replaced them too. whole thing sits way more securely now than it used to.

[norwichphoto]

Is there anything special about the electric after-run pump underneath the inlet manifold? Put 12v to it and was expected to hear it whirr….

Does it have a coolant level sensor inside the pump?

[Shoppinit]

Just a dumb 12v pump IIRC

[norwichphoto]

It would appear mine is a dead dumb 12v pump…

[norwichphoto]

Hoping that a Pierburg replacement pump is suitable. Audi wanted £ 278 for a genuine one. Pierburg one was £ 80 via Autodoc.
Autodoc is usually cheaper if you use their smartphone app, so I'm doing it on a web browser with a coupon finding plug in, and then transfer the valid discount coupon to the app.

[Shoppinit]

Those pumps die a silent death. I bet half of the RS6s on the road have duff one and the owner is none the wiser. As long as you let your turbos cool down before stopping the engine, which I'm sure all good owners are doing anyway, then it doesn't really matter.

Still, for £80 it's a no-brainer, if you can get one. Can you post up the Pierburg reference?

Good tip about using the app. I'll have to try that. I need a starter motor for the M3.

[norwichphoto]

Pierberg 7.02074.75.0
It cross references to the same part number, albieit with a different suffix letter - so a bit of a gamble, but can sent it back if obviously different.

Last order from Autodoc was £ 86.52 after VAT and carriage. Same order through their website would have been £ 107.20. They probably want to drive people to their own app and are discounting this method at the moment, so maybe in the future the discount will be reduced.

[Mɐʇʇ]

Those pumps die a silent death. I bet half of the RS6s on the road have duff one and the owner is none the wiser. As long as you let your turbos cool down before stopping the engine, which I'm sure all good owners are doing anyway, then it doesn't really matter.

They're pretty quiet even when running - I pretty much have to have my ear on the intake manifold to hear it. I bought a spare a few years back "just in case", but it still seems to be working.

But I think your main point, and the point of me replying is YES - if you've been ragging it, drive gently round for a bit to let everything cool down and let it idle a little before switching off. And change your oil regularly. IMVHO this'll more than mitigate whether or not the pump works.

[norwichphoto]

I didn't realise it had a pump, but now I know its not working, I can't ignore that.

[Felix2566]

plus easy to do now your in there!

[norwichphoto]

Couldn't do anything this weekend as bits didn't arrive in time, although an email from Evri saying they tried to deliver but no-one was in ( there was ).

Hopefully get the job finished this weekend and then can think about what to do about the tyre shoulder wear.