Head Gasket or Turbo?
 

Keep in mind this truck has seen 1680* EGT and 52 lbs of boost again and again for 90,000 + miles so I am amazed it lasted this long.

O.K this morning the temps were about 6 Degrees out when I started the truck. Not plugged in as usual, went to high idle ... then 3 cylinder run for 15 minutes.

Hoped in and went off to work .. no problems no smoke ... running just the same as always.


5 Hours later hoped in leaving work, started it, went to high idle and I noticed a bit of blue whisping by the truck. Figured ehh it's cold. Gave it some time and started driving out the parking lot. By the time I made it 200 feet I was POURING blue.

Drove it home (Mainly OFF boost) and when off boost Smokes like a bastard. On boost it's normal sooty for what I have in it. (Edm's DTT blah blah GARRETT Stage III roller bearing turbo)

I just got it home so I have NOT poped the cap to look at the anti-freeze for oil, Nor the outlet side of the turbo piping.

I am leaning twards Head Gasket as off boost is fine, at idle it is BAD, under boost = O.K.

Reason I am thinking this is under no throttle / coast we don't make vacuum to draw oil in (Doesn't mean oil pressure can't override cyl presssure tho) But with the exhaust brake I can throw blue smoke like a Blue Angel

I guess I gotta go an look at what is UPstream of the head (I.E Turbo piping) before I get too nuts here.

im thinking head gasket

Or worse, scored cylinder.

is it possible (I just thought of this) That my Crank Case Vent tube is frozen? It dumps past the Transfer case and If that is plugged then the crankcase would be pressurized forcing oil back UP by the rings?

yep it would

yeah it could be but i highly doubt it, that would be an easy thing to check, park it in front of a torpedo heater and thaw it out and see if stops...im thinking headgasket

Well My dad's 97 12v did something similiar to this. Thought it would start and idle fine but it would have No Power and any attempt to go more than 1/3 throttle or so would send smoke pouring out of the exhaust. Turned out the turbo shaft twisted and broke right behind the turbine wheel. I know Garrets are supposed to be pretty sturdy but I'd pull the turbo and check it anyways. My $.02