2005 Chrysler Crossfire Owner's Manual - Page 164

164 STARTING AND OPERATING FUEL REQUIREMENTS Your engine is designed to meet all emissions regulations and provide satisfactory fuel economy and optimum performance when using high quality unleaded gasoline having an octane rating of 91 or higher. DaimlerChrysler Corporation requires the use of 91 octane or higher premium fuel to minimize the potential for engine damage. Light spark knock at low engine speeds is not harmful to your engine. However, continued heavy spark knock at high speeds can cause damage and should be reported to your authorized dealer immediately. Engine damage resulting from operating with a heavy spark knock may not be covered by the new vehicle warranty. Poor quality gasoline can cause problems such as hard starting, stalling and stumble. If you experience these problems, try another brand of gasoline before considering service for the vehicle. Over 60 automobile manufacturers around the world have issued and endorsed consistent gasoline specifications (the World Wide Fuel Charter, WWFC) to define fuel properties necessary to deliver enhanced emissions, engine performance, and durability for your vehicle. DaimlerChrysler Corporation recommends the use of gasolines that meet the WWFC specifications if they are available. Reformulated Gasoline Many areas of the country require the use of cleaner burning fuel, referred to as "Reformulated Gasoline". Reformulated gasolines contain oxygenates and are specially blended to reduce vehicle emissions and improve air quality. DaimlerChrysler Corporation supports the use of reformulated gasolines. Properly blended reformulated gasolines will provide excellent performance and durability of engine and fuel system components.