There should be no vacuum in the induction system after the turbo but a positive pressure.Yes, I understand it is not supposed to have oil in it and I understand that a vacuum should not pull oil out of the turbo. But in my case the failing turbo does indeed spit oil when exposed to vacuum, which ends up in the IC. The vaccuum was stronger with the cracked IC, in my understanding, because instead of pulling the pressurized air (say .3 bar of positive pressure and dropping it to -.1) it was pulling atmospheric pressure down to, say in this case, -.4 bar. I understand that ideally I’d need to address it as it is the root cause, but I do not want to spend on a turbo what would be in my country the amount of money I spent on my car, especially because I am upgrading soon. Anyways, I solved the check engine problem.
Ran the clearing cycle (top right pin in the breaker box short to ground + 2 full throttle presses), but nothing happened. I then disconnected the battery and ran the cycle before the DPF light had a chance to appear. The cycle finished about 80 minutes in and no lights are on the dash anymore .
If you have got a vacuum then your turbo isn't turning. Any oil in the IC is from leaking turbo seals, so as Talon said look at your turbo.
You do not 'pull' pressurised air.
A cracked IC is more liable to blow air out to atmosphere as its pressurised or should be if your turbo is working. You do not get a vacuum and a pressure in the same enclosed space.
A turbo charger is an exhaust gas driven air compressor, the air compressed heats up and so has to be cooled by passing through the intercooler (put your finger on the end of a bike pump and try pumping, your finger will become hot) conversely expanded pressurised air cools down and can form frozen condensate. This pressurised cooled air then feeds into the cylinders as the air inlet valves open. The greater mass the of air the more fuel that can be injected and hence more power produced. Inject more fuel without the corresponding increase in air and you produce black smoke.
Do you get black smoke when you floor the accelerator or any turbo lag?