As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE THE LEFT ENGINE WAS IN OPERATION, THE LEFT PRESSURE REGULATING SHUTOFF VALVE WAS CLOSED. A STRONG ODOR WAS ASSOCIATED WITH IT. THE AIRPLANE WAS REMOVED FROM SERVICE (GROUNDED) AND THE LEFT ENGINE WAS OPERATED WITH NO DEFECT FOUND. THE CAUSE OF THE ODOR WAS NOT FOUND.