Runs Smooth, But Blows Blue Smoke...What Could It Be?

[torbs]

ok, i have a 90 awd and it runs good and boost fine, but theres basically a constant stream of blue smoke out of the exhaust. its medium thinkness id say, cant really tell beings that its -20 outside...but anyway, im thinking its either rings, valve seals, or the turbo is blowing oil...remember, it runs fine (except for some idle surge, doest really bother me that much, just thought id mention it) and it goes through a quart every 300 miles or so...or about once a week...i hope its not rings...what are your opinions? anything would be helpful

 

[I-luv-em-all]

if the idle stumbles or surges, that can mean that the compression is low or uneven. do a compression test to be sure. do a simple shaft play check first that will cross off another possiblity.

 

[torbs]

there doesnt seem to be much shaftplay and the compression is 150 across the board...also, it looks like the blue smoke is coming out of the exhaust...i can tell this by a half cracked weld on the top of my ex. mani (very weird wg setup), but it does smoke blue out of that...it seems to shoot out more blue after the car has been idling for awhile too...BUMP

 

[I-luv-em-all]

if the turbo doesnt have any oil in the compressor side, and the compression is 150 all the way across, it must be valve seals. also replace the PCV valve i heard can cause a little smoke and they are cheap too so might as well, also get a valve breather or catch can, sumtimes oil can shoot out of the valve cover and cause oil to go inside the intake pipe also causing a little bit of blue.