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Discussion Starter · #1 ·
Got an AUM with an oil catch tank venting straight to atmosphere as shown in the pic below:



Also removed the combi valve with SAI, n249 and n112 pumps, as well as the charcoal canister. I've vented the fuel tank vent out the back of the car and blocked off the hose from the charcoal canister to throttle body. So all I got going into the throttle body is the charge air from turbo. Idle had been perfect there after for about the last half a year but since last week it's started to get a bit rough - not so bad it stalls on idle which it did do when I first got the engine and the throttle was full of coke. So it's down to a few things now, spark plugs, dirty throttle body or MAF. As the car pulls fine through the gears i'm going to assume it's not the MAF and the plugs were changed about a year ago, so it looks like the throttle body might be dirty again.

Catch tank is doing a good job though, below is a pic of all the crap that it collected:



So maybe it's the accumulation of oil from the turbo to the throttle body? I've had the charge pipe off and had a look to see if there was oil passing by but found there was little/no residue in the piping. I've got a ko4 waiting to go on and I'd like to know whether there would still be oil passing through the turbo if I had it completely rebuilt/hybridised, or do all turbos pass a bit of oil through the charge pipes?
 

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This happened to me, kind of.. I took the TB off but it was spotless, didn't touch it and re-fitted it and then did an alignment on vag-com. Perfect ever since [y]

You've capped off the vac inlet right behind the dipstick?
 

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Discussion Starter · #3 ·
Yea I capped off the big one behind the dipstick and of the two on the end of manifold, one feeds the bov and one feed the fpr. I'm at uni for the week and don't have any tools with me so Im only presuming it's dirty, cant do anything until the weekend.
 

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Could it be oil that had settled in the intercooler previously, and has been slowly drawn up over the TB? I know of people that have literally poured the oilyness out of their SMIC's!

Turbo's will begin to leak a bit of oil if you let the engine idle for a very long period of time. As the piston rings on the shaft and slinger rely on a pressure differential across them to prevent leakage.

I guess the first port of call is to see if the TB is actually dirty, then whip off the IC and see what's in it.
 
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