Slow turning over and clicking is usually a sign of a weak battery, loose or dirty battery cable end connections on the battery, corrosion in the battery cables or a failing starter...usually in that order. A parasitic draw could also be present causing the battery to drain when the engine is not running. So, check you battery cables and connections, have the battery tested and check the charging system while your at it. It still wouldn't hurt to replace that fuel filter, but it wouldn't cause your engine to turn over slow.