Outer Limits 4x4 Board

hi guys.
i have a 2.8 turbo diesel rocky F75. i took it for a highway drive for an hour or so the other night. when i got home it was idleing very rough. the next morning i pooped the hood and started it and there was quite a bit of exhaust smoke in the engine bay and still was idleing rough. the two things i can think of are exhaust mainfold gasket or head gasket. if the monifold gasket was blown out, would it cause the car to idle rough? there is no loss of power over 1500rpm ands i didnt realise there was a problem until i pulled up. there is no oil in the water or vice versa. any ideas?

If the exhaust manifold gasket was leaky you would probably notice it under normal driving, not just idle. You could probably hear it too.
Have you lost any boost pressure?
Are you sure its exhaust smoke in the engine bay?
You should try to pinpoint where it is coming from, either by seeing the smoke coming from somewhere, or trying to hear the noise, if any.

the smoke is coming up between the rocker cover and the turbo. i cant really see where is it coming from. there is a very slight tsst, tsst, tsst, tsst noise coming from over that way but cant see or hear where. the smoke is bad at idle but hold it at 1800-2000 rpm and it clears up alot but still runs a bit rough