Where is the fuel filter located on a 1999 Mercury Cougar? wwwers››American Cars›Mercury›Mercury CougarBetween the fuel tank and the engine. Get under the car and trace the lines. You will find it. Answer Jack up the right rear side of the (may not have to if you are skinny. Fuel Filters for 1999 Mercury Cougar for sale | eBay www››Car & Truck Filters›Car & Truck Fuel FiltersFree Shipping on many items across the worlds largest range of Fuel Filters for 1999 Mercury Cougar. Find the perfect Christmas gift ideas with eBay.