2009 Ford Mustang Owner Guide 1st Printing - Page 265

Maintenance and Specifications At the next opportunity, safely pull off of the road, remove the fuel filler cap, align the cap properly and reinstall it. The check fuel cap light or "check fuel cap" message may not reset immediately; it may take several driving cycles for the check fuel cap light or "check fuel cap" message to turn off. A driving cycle consists of an engine start-up (after four or more hours with the engine off) followed by city and highway driving. Continuing to drive with the check fuel cap light or "check fuel cap" message on may cause the light to turn on as well. If you must replace the fuel filler cap, replace it with a fuel filler cap that is designed for your vehicle. The customer warranty may be void for any damage to the fuel tank or fuel system if the correct genuine Ford, Motorcraft or other certified fuel filler cap is not used. WARNING: The fuel system may be under pressure. If the fuel filler cap is venting vapor or if you hear a hissing sound, wait until it stops before completely removing the fuel filler cap. Otherwise, fuel may spray out and injure you or others. WARNING: If you do not use the proper fuel filler cap, excessive vacuum in the fuel tank may damage the fuel system or cause the fuel cap to disengage in a collision, which may result in personal injury. Choosing the right fuel Use only UNLEADED fuel or UNLEADED fuel blended with a maximum of 10% ethanol. Do not use fuel ethanol (E85), diesel, methanol, leaded fuel or any other fuel. The use of leaded fuel is prohibited by law and could damage your vehicle. 265 2009 05+ Mustang (197) Owners Guide USA (fus)