So as the title states, I get a strong burnt oil/exhaust smell in the cabin after boosting my '91 940 turbo sedan.

At one point, I could see the fumes when the light hit them the right way in front my me.

The exhaust does only has a small leak but in front of the rear most muffler. Is there a good way to check to see if the exhaust manifold has cracks (as I know they're common) without taking it off? (This seems to be the most likely culprit).

Also, I've read about the cowl/hood seal not sealing properly, but mine seems ok, it dips down a little at the passenger side, but I doubt that would be enough for fumes to flow in that heavily.

I'd also like to mention I checked the PCV nipple, and it looks clear enough. Would a leak in the PCV system, say where it meets the turbo inlet hose (that connection seems questionable) cause oil fumes to be pulled into the cowl?

I'm going to pull all the cold side hoses (and pcv piping) inspect and clean it all out. Hopefully something will reveal itself while I'm there.

Still going to inspect the manifold for cracks. The turbo and manifold joint has some white deposits, but they don't look fresh. I need to inspect the shaft play on this baby 13c too, so I may be solving the issue and upgrading at the same time. I'd like to hear some suggestions on what else to look out for though!