Originally Posted by
xr4x4rs
or before doing a compression check as that requires turning engine over so could do more damage if its been starved of oil
take your dizzy out and put a drill on the allen key bit, this will spin the oil pump to see if your getting oil in the top of the head, so just take your turbo oil feed off and see if any oil comes out
also if you turn your igntion om see if you have an oil light, as when you spin the oil pump with a drill the light should go out, this a is a sign that you are getting oil pressure above 7psi
Out of all the suggestions here, do this first. Its the most engine friendly way of proving oil pressure. Plus you don't have to really remove much from the engine to perform the test.
Once you've proved you have oil pressure, check the all your electrical connections - could be something stupid like a crank sensor fault causing the rough running. If all thats ok, check the timing, make sure it hasn't jumped a tooth or anything.
Then try compression tests etc.