2010 Mercury Grand Marquis Owner Guide 2nd Printing - Page 250
2010 Mercury Grand Marquis Manual
Page 250 highlights
Maintenance and Specifications Do not be concerned if your engine sometimes knocks lightly. However, if it knocks heavily under most driving conditions while you are (R+M)/2 METHOD using fuel with the recommended octane rating, see your authorized dealer to prevent any engine damage. 87 FFV engine (if equipped) If your vehicle is flex fuel capable, it is designed to use Fuel Ethanol (Ed75-Ed85), "Regular" unleaded gasoline or any mixture of the two fuels. Use of other fuels such as Fuel Methanol may cause powertrain damage, a loss of vehicle performance, and your warranty may be invalidated. It is best not to alternate repeatedly between gasoline and E85. If you do switch fuels, it is recommended that you add as much fuel as possible-at least half a tank. Do not add less than five gallons (18.9L) when refueling. You should drive the vehicle immediately after refueling for at least 5 miles (8 km) to allow the vehicle to adapt to the change in ethanol concentration. If you operate your vehicle 50% or more of the time on ethanol, you should follow a different maintenance schedule. In addition to this, if you exclusively use E85 fuel, it is also recommended to fill the fuel tank with regular unleaded gasoline once every 3,000 miles (4,800 km). See scheduled maintenance information for more information. Fuel quality Do not add aftermarket fuel additive products to your fuel tank. It should not be necessary to add any aftermarket products to your fuel tank if you continue to use high quality fuel of the recommended octane rating. These products have not been approved for your engine and could cause damage to the fuel system. Repairs to correct the effects of using an aftermarket product in your fuel may not be covered by your warranty. Many of the world's automakers approved the World-Wide Fuel Charter that recommends gasoline specifications to provide improved performance and emission control system protection for your vehicle. Gasolines that meet the World-Wide Fuel Charter should be used when available. Ask your fuel supplier about gasolines that meet the World-Wide Fuel Charter. 250 2010 Crown Victoria (cro) Owners Guide, 2nd Printing USA (fus)