What was found
THE PREVIOUSLY WRITTEN UP STRONG ODER SMELL IS STILL APPARENT DURING TAXI, CLIMB, AND DESCENT EVEN WITH LH RECIRC FAN DEFERRED. (FLIGHT 3979 - FILED CLOSED)PERFORMED TROUBLESHOOTING FOR ODD ODOR PER ERJ175 FIM TASK 21-20-00-810-801-A. FOUND NO SIGHT OF SMOKE OR ODD ODOR FROM OUTSIDE OF THE AIRCRAFT. FOUND NO OIL SEEP FROM APU AREA. FOUND NO SMELL UPON THE CEILING LIGHTS, SIDEWALL LIGHTS, READING LIGHTS DURING INSPECTION. FOUND NO SMELL UPON THE FWD AND AFT GALLEY AREA, FWD AND AFT LAVATORY, FWD LH AND FWD RH ENTRANCE AND AFT LH ENTRANCE AND AFT RH ENTRANCE. DURING APU RUN, FOUND ODD ODOR COMING FROM COCKPIT AREA. PERFORMED CHECK OF THE AIR COND/PNEUMATIC DURING ENGINE RUN AND FOUND SMELL COME ON WHEN THE LH PACK WAS ON WHEREAS WHEN THE RH PACK, XBLEED, BLEED 1, BLEED 2, AND BLEED APU, NO SMELL CAME ON. PERFORMED GVI OF THE AIR CYCLE MACHINE IN REFERENCE TO ERJ175 AMM 21-51-05. FOUND NO LEAKS, NO CRACKS, AND NO DAMAGES AT THE TIME OF INSPECTION. PERFORMED GVI OF THE RECIRCULATION FAN FILTER IN REFERENCE TO ERJ175 AMM 21-24-02. UPON GVI, FOUND THAT THE LH RECIRCULATION FAN FILTER TO BE DUSTY AND DIRTY. REMOVED AND REPLACED LH RECIRCULATION FAN FILTER WITH A SERVIC