[skyship007]

Originally Posted by skyship007

The old pre ECU/common rails diesels did smoke a bit on start, but the modern ones don't!

@OP:
When were the air intake and EGR last cleaned ??
Have you checked the crank case vent system is not blocked ??

How much oil is this car burning?
Any coolant loss?
When were the oil & filter last changed and what did you use ??
Have you checked the oil level and done a finger rub inspection ??
,
The engine is also rough running at cold idle, so this does not look good. Wild guess, but HG failure, bad rings, blown turbo or wrong oil in use.

Seriously thin oil caused by gummed up injectors (It won't show a code) and too many short trips or time at idle and a poor quality 0 or 5/30 is in third place, along with a half blown turbo oil seal.

The key question would be, is the coolant level going down or the oil level going up and does it smoke when started ??

If you want to know about the HG, one easy way is to send a 200 ml sample of used oil (Must be at least 3K miles old) to Blackstone Lab Inc. Their analyst will let you know if the HG or an injector is leaking. Volvo anti freeze contains both Sodium and Potassium compounds which are rare in engine oil (Castrol GTX and Valvoline Maxlife do contain Sodium), so they should both show below 10 ppm after 10K miles.
If the injection system has a fault, then the flashpoint of the oil will drop and a direct test for fuel will result in a warning.
Bad rings dump Chromium into the engine oil, but there is no easy way of checking an EGR from a UOA report. A blocked EGR or CAT can cause a check engine light.
A blown turbo will show up as a high Copper reading, as the steel bearings in a turbo are the only ones in a diesel that contain Copper.