plugged oil return would effect turbo lubrication and probably blow the seals in the turbo..

as for oil in the air intake?! your turbo has a blown seal and needs to be rebuilt ASAP.

oil coming into the intake of a diesel is very dangerous. if enough gets in there and actually makes it to the engine it can cause uncontrolled fueling and a runaway even with the injection pump, lift pump, and computer shut down, as it will be feeding on oil from the turbo until the engine is out of oil...

if that happens you need to block off the air intake immediately before the engine goes boom...
get that oil leak fixed ASAP.

as for your dyno numbers...they sound "corrected"



we do create boost at cruise speeds unless we are coasting.

I run about 5-10psi cruising at 68mph on the highway. a stock truck would do about the same if not more...because of my turbo size at low load situations my boost does not come up much...once I put a load on her boost really comes up, where a stock turbo will spool much faster and spool with minimal load. makes my want to change to a tighter exhaust housing on my secondary to get it to spool a bit quicker.

also ATS turbo's are not known for their great spool...far better options out there for less coin...

 

also: if you have a K&N filter on your "cool air intake" throw it away and get a dry filter like AFE..same size and shape, but better filtering and not oil soaked.

K&N's and other wet filters are known for putting oil in the intake on forced induction engines.

the turbo will quite literally suck all of the oil off of the filter and into the turbo compressor and intake gunking everything up. at that point the filter is useless as it will let dust through as that was what the oil was there to stop...

never ever put K&N filters on diesels. gasoline's are fine as they are not forced induction and the ones that are don't pull enough air through to suck it off the filter...

typical gas boosted engines are ~5psi where diesels start off stock (+ a fueling mod) capable of ~35psi. huge difference...

 

Ever take that truck off some sweet jumps like on Knight Rider?

I always loved it when the car did that Turbo Boost thing. The bad guys never knew what to do!!!

 

thanks jigabop. everything you say makes sense. Like your's I sure do remember running 65, I used to be right at 5psi. Now it will come up if I step on it, but it seems to me to be 5psi below through the range. The oil in the intake is very minor, but noticable. I asked ATS, they said 100% normal. I trust everyone, but always cut the deck, so I contacted Alamo Turbo service here in WA, and they said the same thing. You will get a small amount of oil through an intake. You mentioning the Oiled filter might make sense, because I just cleaned and re-oiled it not a week ago. Sounds like I need an AFE. I always heard they were better anyway, but I've not had any dirt buildup in the tubes. I was told that if you farm, or gravel road it a lot, AFE is the only way to go. I'm going to check the oil return tube, but I doubt thats it. The other thing I will do quick is put a different gauge on the intake and see if it matches the Autometer. Maybe my gauge has gone 5psi to the south???
Traffic light starts without romping it are normally 15 to 20 easy. A 10k trailer, and i will hit 30-35 up hills. but right now it just seems 5 lower than I ever remeber. The exhaust is running the same temp as always, so maybe I'm making air, and just not reading it.
I will repost after next checks.

 

maybe boost line is pinched or leaking on your gauge

also do not deal with those guys....(bold in your post)

they will F*ck you over...

I have been f*cked over by them already and so have dozens of others...

the turbos they build/rebuild are **** and fail within a month and they refuse to warranty them and blame the vehicle they are on, or the installer.

I had them build me a hx 40/35 hybrid with all brand new parts, they built it, and less than 1 month later the bearings blew in the turbo and the compressor started grinding. They said my oil was contaminated, then I lab tested it and lab agreed contaminated with metals from THEIR BEARINGS. that material is only found in turbo bearings as no other part of the motor contains brass/bronze. then they tried to say my truck has low oil pressure...

they just made excuse after excuse...btw I haven't changed anything to modify oil pressure and I have ran compound twins off it flawlessly now for over 2 years. at the time I was running a single turbo...low oil pressure...
60psi+ oil pressure and if you pull the line it will shoot oil clear across the shop floor...

another dude had a powerstroke and got a turbo from them...turbo blew on the test drive after the install...again blamed the truck and the installer refused warranty...

just some buyer beware...i wouldn't take a free turbo from those bastards.

 

I have read somewhere that a minute amount of oil residue in the intake pipes is normal. Can't remember why it happens. I am new at this.


Something about it being vaporized in one place and then condensed again with the cold air charge.

 

That would make sense. Oil that vaporizes can only do two things. Burn or condense back. And it should not bee very much. Seems I have read this years ago, but memory is a beach at my age.