What was found
OIL ODOR IN ALL OF THE CABIN. ACFT GROUNDED. FOUND EVIDENCE OF DE-ICING FLUID INGESTION INTO AVIONIC VENT FILTER AND FAN BLOWER E/E VENT, COMPLIED WITH TSM 05-50-00-810-831-A, REPLACED THE AVIONICS VENT FILTER IAW AMM 21-21-41, REPLACED THE AIR CONDITIONING RECIRCULATION FILTER IAW AMM 21-26-43. OK FOR SERVICE. REPEATED NEXT DAY. AFTER RUNING BOTH ENGINES AT IDLE POWER, HAD AN ODOR IN FWD AND MIDDLE CABIN. IAW TSM 49-00-81-810-8701-A, REPLACED THE APU IAW AMM 49-11-11. OPS & LEAK CHECKED GOOD.