Low boost, high fuel consumption and 00561 fault

[andy10v]

I didn't do a full boost test with the kit, I just wiped all the boost hoses that I could reach with a soapy cloth then ran the car, on the basis that anything leaking would show up with bubbles.

If the car is idling and you are checking the intake would be under vacuum, so it would suck stuff in.

[LitD]

I'm starting to feel like Baldrick. I have a cunning plan, it's only flaw is me not understanding how the world works Oh well, back to the drawing board.

On the up side, I've made it to 2 pages

[macspring]

You're also in for a shock if you think 21mpg is high

That was my thought also, wish I could achieve that around town.

[UrS4boy]

I'm starting to feel like Baldrick. I have a cunning plan, it's only flaw is me not understanding how the world works

But Baldrick's plans were *sly* and cunning *AND* involved the all important turnip. This is your problem, no turnip.

Well in this case, no pressure. It is a BOOST pressure test, not a vacuum test.

Read this again, I am pretty sure it says pressurize the system to about 15 psig (1 Bar(ish)) for the test.

http://www.s2forum.com/forum/showthread.php?t=63987

Yes it does: "Testing for boost leaks involves introducing controlled pressure, i.e. 10 to 15 psi from an air compressor into a non-running engine, with a pressure testing bung, such as shown in the diagram below and various other hoses plugged off (as appropriate to that test). "

[Nuno Cristiano]

I have same error in my RS2 but not have problems of performance.

[bilko0795]

Ok, assuming a boost leak for a min, can you use an ABY boost test kit on an AAN? And cross-check with Bilko, that was an ABY kit you had wasn't it?

Thanks all

Rob

Yes Rob i have the loan of an Aby kit.

[UrS4boy]

Yes Rob i have the loan of an Aby kit.

Which should work on an AAN as well.

[bilko0795]

Which should work on an AAN as well.

Wasn't sure if the middle size bung would fit the I/c to throttle body hose as it's wider on the throttle body end compared to the Aby hose.

[prj]

You do not need to block off the throttle body!
That's a horrible idea, because 99% of boost leaks are from the vacuums and other systems connected to the inlet manifold. I don't even know who ever came up with blocking the throttle body, but they should be shot.
I have received a numerous amount of cars for mapping where the owner claims it's leak leak free by plugging the throttle body and in fact it won't hold any pressure from the inlet manifold.

All you need is:
* Remove MAF, plug it with a bung that has a tire nipple in it.
* Remove the PCV hose from the MAF to Turbo hose and block it on the MAF-Turbo hose end, leave the other end be.

That's it. Do NOT plug anything else, as else you will not find leaks.

[Avantus]

Absolutely true abou those vacuum lines.

I'm now replacing all the little hoses connected to the rear of the IM since they are all gone hard and perished. Also that one way valve towards aircon recirc and diff/lock should be checked and can cause boost loss.

[220bhp]

Dmitri, didn't you also block the hose to the waste gate when you did my car.
Or was that just for your special customers

[prj]

Good point Lou.
You can block the hose to the wastegate, so that it does not hiss.
A minute amount of air will otherwise escape through the wastegate to the exhaust and cause a slight hissing sound. All stock wastegates hiss, otherwise they would seize when they heat up.

This is optional though, as it makes very little difference to the speed of the boost escaping, just it is nice to have it quiet if you are listening for audible leaks.

[bilko0795]

You do not need to block off the throttle body!
That's a horrible idea, because 99% of boost leaks are from the vacuums and other systems connected to the inlet manifold. I don't even know who ever came up with blocking the throttle body, but they should be shot.
I have received a numerous amount of cars for mapping where the owner claims it's leak leak free by plugging the throttle body and in fact it won't hold any pressure from the inlet manifold.

All you need is:
* Remove MAF, plug it with a bung that has a tire nipple in it.
* Remove the PCV hose from the MAF to Turbo hose and block it on the MAF-Turbo hose end, leave the other end be.

That's it. Do NOT plug anything else, as else you will not find leaks.

Thanks for that info that's maybe why i can't find the leak on my car still.

[UrS4boy]

You do not need to block off the throttle body!That's a horrible idea, because 99% of boost leaks are from the vacuums and other systems connected to the inlet manifold. I don't even know who ever came up with blocking the throttle body, but they should be shot.

Bit harsh?

Blocking off the throttle body and ISV inlet hose play out in only 2 of the 6 options I put forward for consideration as boost testing OPTIONS (Options 3 and 6). The different options allow for the isolation of areas of potential leaks, including NOT pressurizing the PCV system backwards.

http://www.s2forum.com/forum/showthread.php?t=63987&highlight=AAN+boost+leak+testing

[prj]

The different options allow for the isolation of areas of potential leaks

You do not need to isolate anything. All this is under pressure each and every time you are under boost. So it only makes sense to pressurize everything.

including NOT pressurizing the PCV system backwards.

The PCV system never gets pressurized this way. Ever. If everything you put in leaks out of the PCV then you know the one way valve under the manifold is shot.

Pressurizing any other way than plugging the MAF, blocking the PCV outlet on the MAF turbo hose and maybe pinching the wastegate hose is a complete waste of time. Unfortunately very commonly done in the UK due to being wrongly advocated on this forum, and results in me having to fix tons of leaks before mapping two thirds of the cars that are supposedly "pressure tested".