Where is fuel filter for a 2003 mazda 6 located - Fixya Jun 29, 2014The fuel filter on most Mazda cars can be located on a bracket in the left rear of the engine compartment, next to or beneath the brake master cylinder fluid reservoir or as part of the fuel pump assembly. The filter on Mazda3 models is part of the fuel pump assembly. The fuel filter is part of the pump assembly. 2003 Mazda 6 Fuel Filter: I Believe That I Have a Clogged I believe that I have a clogged fuel filter and wondered if there is a way to clean or replace only the filter part of the overpriced $350 fuel pump assembly. Thank you so much in advance for your input. P.S. Any insight on why Mazda would have coupled the filter with the pump?