Sci-fi_Wasabi

EHLO, thanks for the advise. Did you replace it yourself? i'm wondering if you used one of those crimp hose clamps or just went with a small spring clamp like on a radiator hose to attach the oil return pipe. Wondering if you were able to do it without removing the throttle body,,, though your S8 would be a longer engine i think.

EHLO

I didn't replace the tube (1), but just rolled up the braided hose that covers it towards the right end (left side in picture) and patched it with two part epoxy.

mishar

Just popped in my mind. If your mechanic spilled some oil it could end on the belly pan and later on your floor. Let's be optimistic.

MP4.2+6.0

My W12 set up is different, but I just changed a part in the W12's analogous system. It used two single use pinch clamps. I just bought those at the same time as the suction (aka suck) valve needed on mine. You squeeze them tight either with a dedicated tool, or more likely the similar CV joint tool; they have versions with jaws either on the end (face), or along the side depending on the access you have. If you are careful, you can squeeze them tight with regular butt nose wire cutters too; almost better if they are somewhat worn and dull. BTDT w/ butt nose cutters, probably literally 20 times over the years before I bothered to buy a set of real CV joint clamp ones. Frankly, if you don't care about a strictly OE look, you can also use the right size standard screw down hose clamp.

On the throttle body, I have pulled those on both a 4.2 and 6.0. When I have the luxury of time, I pre-order the gasket to avoid any possible vacuum leak. Otherwise, maybe just a very light wipe of some gasket sealant.

Sci-fi_Wasabi

It's just too tight a fit to use the crimping tool, any problems replacing with a spring type hose clamp (like the black ones used on a lot of coolant hoses) instead of the screw down ones, or do you thing they don't work as well, which is why they didn't put the spring clip there in the 1st place.

I got the throttle body off so far, its a bit oily in the intake area past the throttle body...normal?

MP4.2+6.0

Any clamp that mechanically seals it against a vacuum leak is fine. They use the single use crimp ones because the work is done on a line, often by machines and of course with parts and things like hose subassemblies not yet in the vehicle. FWIW, I could get in there with the tool, but I pre clamped one of the connections/hoses first by pulling the other end of the hose. And indeed the other end used exactly the black re usable clamp you use pliers for to remove.

A little oil in the manifold at the bottom just past the throttle body seems normal. I have pulled one on my W12 a couple of times to get at nearby parts and there is typically a slight amount of oil there. My motor burns essentially zero at 106K miles; I have never added even part of a quart bottle between oil changes. I think the oil comes from the valve cover vapor set up.

Sci-fi_Wasabi

Thanks for the advice MP4.2, I'll go with the spring clips then.... much easier than crimping.
One dealer wants $1180 to do this, another wants $430. I'm tempted by the $430... but I know when I do it myself, I'll take care of little stuff, like replacing the throttle body gasket as you suggested.

Sci-fi_Wasabi

Mike 141 requested more info on how to remove the Oil separator. Almost every repair place will say that the intake manifold needs to be removed to replace this, and that would make access easier, but requires more steps.
Beyond the tools most of have to do routine work, I had to get, a long neck curved pliers to get at hose clamps and a Torx key set to access screws in the back of the separator in very tight spaces. I tied a string to the torx key i was using because if it slipped out of my hands it would end up in the dark abyss of the engine bay. i also purchases an assortment of hose spring clamps from the auto parts store.
Remove the engine cover and you will see the general area you will be working in. The oil separator is in the orange square, the coolant adaptor is in the orange oval. My coolant adaptor was also slowly leaking coolant at the top flange. So I needed to take it out too. The plastic becomes very brittle after 3 years of engine heat... i wish Audi would have engineered these as metal, not plastic. just the act of removing the hoses clamps and hoses causes them to fracture. I would suggest having a spare coolant adaptor on available should it crack while working. I took pics of the part numbers for the 09 year a8L.

Sci-fi_Wasabi

Here is a closer pic of the part, with the top coolant hose removed. The orange circle shows where i had a hairline crack where some coolant was leaking, move the other hoses out of the way so you can get you hands in the back of the oil separator.





Ok, to start, detach the air intake hose from the air box and remove the throttle body. There are 4 long torx screws (#16) holding the throttle body onto the intake manifold. See diagram. It is best to replace the throttle body gasket (#14). Detach the throttle body from its wring harness and stick it somewhere save in a plastic bag. Later take q-tip & appropriate cleaner and clean the build up off of the flap.



Next is Mishar's diagram. #5 is the object we are removing. Pulling off hose 1 is easy, just some squeezing on the ring clips with your fingers and pull. Getting hose #7 off of the oil separator was very difficult because, the hose is attached by a one use crimp ring from the factory... you have to get at it at just the right angle to unravel the crimp... you will most likely damage the flange it attaches to on the oil separator, but no problem if you are replacing it. This is where you need the long neck curved tip pliers.



There are 3 torx screws in the back of the oil separator that you can't see, you must find them by feel. you can't get a ratchet back there, so you need to use the torx key to very patiently unscrew each one. you can only turn the key a few degrees at a time so it will take some time and hurt your fingers, but it will come out. Maybe one of these little thumb ratchets would have worked. tie a thread to the key, as you will drop it at some point... and you don't want to look for it in the engine bay. The 3 orance squares show where the screws are.




You have to twist the separator a bit to brake it free from the coolant adaptor it is fitted into. here is how the two attach. (notice how the places where the hoses attach just disintegrated on mine when i took mine off.)



Here is a view from the front with the coolant adapter attached.
I think my oil separator was leaking from the seam in the orange square. You can also see where the port where oil hose attaches to the separator on the bottom. Once everything is detached and it is loosened from the coolant adaptor, you need to play a game of tetris to get this think out from in back of the engine bay. it is possible... i think i moved it to the right a bit, rather then toward the throttle body.



If you are removing the coolant adaptor there are two screws holding it onto the manifold, in orange squares. The lower coolant hose was a killer to get out because it too was attached by a one use crimp ring. you will certainly destroy the part if you are taking it off, as that plastic was very brittle after just 4 years on the car.


The next challenge is finding the spring clip rings that will be the right fit to replace the crimp rings the Audi factory put on. Just be gentle when putting them on, if the are way to tight they will break the plastic. Hope this helps someone.

Mike141

Great instructional write up! Mine is all gunked up near the back, so it must be leaking. I plan to order it and attempt to install next week. I just have to remember to get a bunch of clamps for the hoses. Thanks again!