My condolences about the car theft. Nice that you got it back without it being drestroyed. Startup oil in most non-turbo cars means leaking valve guide seals. This probably isn't the case since volvos don't wear out like that very often. Could be oil seals, but I'm not too versed in turbo oil problems, despite having a turbo car of my own, and coincidentally, going through oil burn problems... About the intercooler, yea thats a good idea to clean out the IC before the cleaning. Take it out of the car, drain the oil out of it if theres a lot, then spray a bunch of carb cleaner (or paint thinner, its cheaper and almost the same thing) into both sides of it, then let it sit for a while then spray it out. should be nice and clean after that. Good luck.
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Isaac Babcock - '83 245DL and '83 244ti, 'Sounds to me like I am right..' -JakeJ