Help! '12 X5 35d puked oil

[Westies]

hey all,

kind of in a situation and need some modified diesel owners' input. Please let me know if there is a more specific diesel sub forum this should be in- I couldn't find one.

Some irrelevant background info: Helping out a friend with his 35d that I convinced him to buy, which he did if I agreed to help him do the work on it. I have an X1 35i (N55, fairly modified) and VW mk4 ALH TDI (big turbo, injectors, etc) that I do most of the work on. We put on a malone stage 2 tune and it has been running great for the last 10k miles, except for the random code every now and then. Hasn't had any issues, holds boost, doesn't leak oil etc.

The problem: Recently we deleted the EGR cooler and valve, everything went smoothly. Installed race pipe, coolant line blanks, capped vacuum line for cooler, and hot side block off plate. Went to load the correct tune when he realized that the tune had a dpf delete, not egr. So after some reading (and my own experience deleting egr on my tdi) we flashed to the stock map for his drive home where he would load and flash the correct tune. We proceeded test drive it, got up to temp and everything ran great, no issues whatsoever. On the way home though at the end of his 25 minute (20ish mile) drive, he noticed smoke coming from the rear of the car. Turns out it had puked oil from somewhere near the turbos, and when going up the steep incline of his driveway, coated the rear of the engine, ran down the ENTIRE outside of the exhaust, all the way to the muffler and coated the entire underside of the vehicle. In all it threw up just over 2 liters of oil. Directly after, he flashed the correct map but didn't drive it. The following day after inspecting I noticed it has very high crankcase pressure, and is blowing smoke out of the filler cap if you open it at all while running (same with breather hose), however it no longer seems to be leaking oil at all, and runs fine with no codes.

Has anyone experienced anything similar?? It looks like it could have leaked from one of the turbo oil lines- it's definitely from the turbo side. There is quite a bit of seepage around the crankcase valve at the back of the valve cover, so I'm assuming it has failed, but I can't imagine this would cause a turbo line, or a turbo for the matter, to blow a seal. I have searched all the forums, and I'm at a loss.

My apologies for the novel, any and all input is really appreciated, thanks everyone.

[RL18]

Valve cover gasket

[denmolee]

I have the same issue with my vehicle. I do not feel any of the modifications you've done "Besties" had anything to do with it. I have 140K on my X5 and it runs great. However, when I was towing a trailer I accelerated hard up to 75 miles per hour pulling out onto a 2 lane road where people top a hill coming at you at 90 mile per hour. Of course, after 65 miles per hour I was enjoying the diesel strong pull of the trailer. I smelled oil burning so looked up at the rear-view mirror to see that I could not even see the highway behind me. I looked like one of those old day mosquito smog trucks that used to drive neighbors. After towing it home I pulled the intake to install new glow plugs. I decarbonized the intake. I blanked off the EGR flaps while I had it out. I cleaned the oil that coated the turbo side of the engine and flowed all the way to the back of the vehicle. It's never left a drop on my driveway prior to this issue. I could not see any problems other than 1 hose was not very tight. Replaced copper seal and put vehicle back together. It has run fine for the last year but of course I know that the problem was not cured.
So, a year later and 12K more miles I've recently cruised a few times above 80 for extended period and towed a trailer again. I smelled oil burning but there was no smoke. However now I'm leaving 3" stains on the driveway each time I smell it. I watched a video of a turbocharger cut in half with the turbine fully assembled sitting in the half shell. The guy explains that the oil enters the top and splits to directly dump oil onto the 2 bearings. Then gravity flows basically through the dry sump back into the crankcase return oil hose. He explained that if the crankcase ventilation system does not keep the engine in crankcase in a vacuum that it'll cause back pressure great enough in the turbo so that when the boost kicks in around 2000 rpms it will suck oil into the inlet of the turbocharger turbine. So I plan to go through the valve cover ventilation back to the inlet of the turbocharger when I find the time. In the meantime, I stay 73 mile per hour and drive with light foot the keep the engine rpms below 2000 rpms so as not to engage the boost. This appears to be working and the oil burning smell and dripping on the drive has stopped.
If you have had any luck in resolving this issue please advise. By the way I also guzzled 2 quarts or more during fogging the highway when towing the trailer. So very much sounds like the same issue you witnessed.