Metering Oil Pump (MOP) Testing/Replacement: Stock 93 Touring FD

Status 4/9/02: Removed the air box and all related hoses. pic
Status 4/11/02: Found MOP wiring harness, tested with ohm meter - it's bad. pic
Status 4/12/02: Removed air pump. pic
Status 4/13/02: Removed alternator. pic

Entire air box removed.

The open ~1 inch hose behind the intercooler was connected to the top (clean air) side of the air box, but it leads to an open end right under the upper radiator hose! Seems like it would take unfiltered air from the engine bay right into the clean side of the air box! What's up with that?