Cleaned the throttle body of an '89 yesterday and noticed oil there, in the intake manifold and in the intake tube after the AMM. Assumed it was from the flame trap exhaust.

So why is the exhaust directed there? Wouldn't it be better if it was directed to the air filter (as in older 240s)? Computerized systems are supposedly sensitive to unmetered air eg. vacuum leaks. Isn't flame trap exhaust unmetered?
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1980 245 Canadian B21A with SU carb but electronic ignition and M46 trans in Brampton, Ont.

Methinks da engineers were concerned about oil fumes condensing ahead of their expensive new hot-wire air mass measurement device. But you saw the oil was rolling down there anyway. Take comfort in the fact they all do it, although the extent of the blowby is certainly variable between zero and 500K miles.

Good question about the accuracy of metering air. I had always assumed the 89+ adaptive systems were capable of accounting for the changes as clearances increased and more crankcase pressure developed. Remember Don Foster's suggestion to measure it using his Magnehelic? His focus was on keeping the net pressure negative, but depending on the vacuum available, the flow might be an interesting qualification as well.
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Art Benstein near Baltimore

Why is it that doctors call what they do 'practice'?