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hi, it's an '03 wagon, brand new VNT-17 from Kerma 2 weeks ago. the person installing it left the actuator rod as it was from the factory. Mity Vac gets it moving at 3.5-4 inches of vacuum, stops at 18.

car seems to develop requested boost only starting at almost 3000 rpm, by then i have to shift(oh yes, it's a 5-speed). until i get my nozzles and a tune in a few weeks, i need to drive. highway speeds lag is way too noticeable. up hill the engine wants to cry...

i want to shorten the actuator rod. the question is how much. what's a safe setting until i get my stage 3 tune? i'm guessing the danger of making it too short is overboost, so how many turns should i do? or at what vacuum should it start to move? thanks...
 

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hi, it's an '03 wagon, brand new VNT-17 from Kerma 2 weeks ago. the person installing it left the actuator rod as it was from the factory. Mity Vac gets it moving at 3.5-4 inches of vacuum, stops at 18.

car seems to develop requested boost only starting at almost 3000 rpm, by then i have to shift(oh yes, it's a 5-speed). until i get my nozzles and a tune in a few weeks, i need to drive. highway speeds lag is way too noticeable. up hill the engine wants to cry...

i want to shorten the actuator rod. the question is how much. what's a safe setting until i get my stage 3 tune? i'm guessing the danger of making it too short is overboost, so how many turns should i do? or at what vacuum should it start to move? thanks...
You are not that far off so I doubt if it is because of the turbo itself. However, I occasionally see these with sticky vanes or actuators even new. It is rare but I have seen 2 of them. Spec is 2.5-3 to start off with a finish about 17-19. Check the vacuum lines. You may need an N-75 or perhaps a maf. Make sure all the hoses are clamped tight and there are no leaks. I would also replace the fuel filter and take a look at the thermostatic t. I have had them fail as well. If all else fails you could drive it 70miles to me.
 

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i have set my actuator to start at right around 2.5 that same night. boost was insane. i loved it. except i had a runaway right after. it was short and i'm back on the road now.

with all the information i have now, i think it's safe to say that it ran away on oil i accumulated in the IC over 600 miles of driving with a very laggy turbo. crankcase pressure after a 5 minute WOT run has helped add to that recipe. in any case, i just finished cleaning/draining/testing/checking and went for a 20 mile drive. i did freak out from the previous incident and reversed the actuator adjustment back to 3.5, maybe 4 inches to start moving the vanes. and btw, they WERE sticking prior to my italian tune. so, over the first 10 miles of driving i went full throttle very conservatively, 10-15 seconds at a time. watching the VCDS graphs, i wasn't catching up with the specified. then during an uphill run i got limp mode and a Charge:Negative deviation fault code. restarted the car and the boost came right back, but my laptop died by then. no limp mode on the way back, but i didn't really give it any load...

i will set it back to 2.5 again, i guess. no more experiments for me for a while...
 

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scary stuff!
quite scary indeed. 90 miles of normal driving - that's just one day - and i've got a cup and a half of oil in the intercooler. about half a quart gone total. the last 25 miles i decided to drive venting right under the hood, to minimize the risk of another runaway. drove like an old lady and ended up with a thick oily mist all over my valve cover and little puddles in the corners. but half a quart through the CCV in one day? it's a little hard for me to believe. so the new turbo is under suspicion again. with a fully warm engine and the lower intercooler hose disconnected, i idled for a bit and then revved it up to about 3k a couple of times. the rag under the disconnected hose remained clean, not a drop. does that mean blown turbo seals is out of the question? or do they give in under pressure or at higher temps? btw, with a shorter actuator rod i was able to hold maximum requested boost for about 10 seconds at WOT in 4th. then it dropped to about 1.5 bar, then even lower, then limp mode. i started thinking i might have a boost leak, since the lower IC pipe has been cut to fit the VNT-17 with an ALH adapter, and it's kind of a stretch fit now. also, i never changed the rubber seal between the plastic and rubber parts of it.

it seems like a simple problem, but i can't figure it out. the oil could be coming from the turbo seals or the crankcase vent. which is it? how can i outrule the turbo seals failure for sure?
 

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You could vent the crankshaft vent into a catch can vented to the atmosphere temporarily. Cap off the intake hose where it recirculated. This will let you see how much is coming from there.
 

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You could vent the crankshaft vent into a catch can vented to the atmosphere temporarily. Cap off the intake hose where it recirculated. This will let you see how much is coming from there.
 

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You could vent the crankshaft vent into a catch can vented to the atmosphere temporarily. Cap off the intake hose where it recirculated. This will let you see how much is coming from there.
did that yesterday. 10 foot clear braided hose directly from the puck towards the rear of the car. drove about 20 miles locally, barely getting to 3rd gear, and guess what - the hose is still clear! either the oil doesn't settle on the inside of the hose or instantly getting blown out with the vapor. or there's just not that much oil coming out. although i haven't tried it at highway speeds yet, i have a feeling that the crank case vent is not the source of high amounts of oil in the IC, but possibly the pressure is a factor in the turbo seals behavior. i have not lost any oil since the mod, so that's kind of relaxing...

got my valve cover replacement bolt set in the mail today, but it's raining all day so i'm pulling it tomorrow. a very knowledgeable member at tdiclub forums suggested cleaning out the demisting pads in the valve cover baffle to improve the CCV operation.
 
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