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turbo off test - yes.

If there's enough engine oil in the cylinders to combust, it will cause a pressure spike which will raise the compression gauge reading. I think the manual says to crank until compression stops rising which could be 10-15 cranks. This is different from a gasoline engine. Also don't add oil to see if it bumps the compression for the aforementioned reason, more info in the FAQ on compression testing.

#3 is low and needs more investigation. The runaway could have been minor enough to not cause damage. The question is where did the oil come from (or what caused the runaway) and why is #3 reading low.
 

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Older cars had a problem with piston blowby oil mist. I don't think it's a direct common cause of runaway on the TDI because this mist settles in the low spots like the intercooler. The problem is more indirect because the runaway starts when the pool of oil gets sucked up.

They sold an oil separator for the older diesels. Not sure how to route the oil line since it's under pressure. I believe any excess oil will burn out once it's running or it'll bleed off. Not sure.
 
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