Car smoking ocasionally

[aade]

Hi. Yes, car is a diesel.
Today I opened the bonnet again to see if I missed something..I noticed a pipe that looked it has a small ripped material on it and when I tried to twist it a little bit it snapped. After that i removed the small part and tried to snap it again using the same force i used when I checked the first time and it wont snap, I tried even harder and no snap..meaning the pipe was already damaged. One end of this pipe goes to egr pressure converter and is black in colour, the other end goes somewere behind the engine..couldn't tell were. There is another red one that looks allright. Do you think this could be the main reason for my car to smoke like that ?.
I will try to attach an image of how this pipe looks like.

I really don't know much about diesels, so I will be careful with what I say.

Since you're suggesting that the behavior changes once you've restarted the car (I presume without allowing the motor to cool down), it says to me that you're reaching a rich condition. If the EGR doesn't work properly, the gases will have to go somewhere and I believe that somewhere is the exhaust in this case. If there's a lot of oil in these gases you'll end up clogging your NOX sensors and possibly also the catalytic converters themselves.

A hose that goes to the EGR, from somewhere on the block (probably similar to a crankcase breather valve or something like that) could make it so that the ECU thinks the EGR is inoperable. If the ECU is getting wonky values from applicable sensors, it's possible that it would try to set a rich condition.

However, if you're burning oil, I would also not rule out compression issues so you should check that. No idea how this is done on a diesel, but it can't be super different from a gasoline motor.

If that hose is broken, replace it. You probably need it anyway. RealOEM.com should give you a clue as to what the part number is.