how could i tell if its the seals gone on the turbo or piston rings on my subaru its had a forged engine rebuild it just smoke heavily on start up and some smoke while runing and accelerating

 

How you got the right oil? My piston rings went on mine quite badly, I took unscrewed the oil cap off and it shot off because of the crank pressure, then I did a compression test

 

have a look at the exhaust tail pipe signs of oil , if there is then very likely to be turbo however to be 100% sure take turbo off and check for play and shaft damage ?

 

If the seals on the turbo have gone you will have oil in the intercooler, whip the intercooler off and look, if oil is present thats the problem. When the seals wear its normally when the car is cold or changing gear.

 

my turbo has just gone on mine best thing 2 do is a compresson test i got about 150 psi on all 4 give or take about 2 psi i think the lowest you can have is about 121 might be wrong gaz