As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORIGINAL CLOSED - STRONG FUMES (NO SMOKE) FIRST IN COCKPIT THEN AFT CABIN. STOPPPED SHORTLY AFTER BOTH RECIRC FANS TURNED OFF. TS IAW FIM 21-00-00-810-804 FROM 804 (A) 2 THRU (D) 2. NO FUMES NOTED. R&R LT RECIRC FAN FILTER I/A/W AMM 21-25-01-4