2004 Dodge Neon Owner's Manual - Page 144

144 STARTING AND OPERATING Malfunction Indicator light to illuminate. The manufacturer recommends that you try a different brand of unleaded gasoline having lower sulfur to determine if the problem is fuel related prior to returning your vehicle to an authorized dealer for service. Fuel System Cautions CAUTION! Follow these guidelines to maintain your vehicle's performance: • The use of leaded gas is prohibited by Federal law. Using leaded gasoline can impair engine performance, damage the emission control system, and could result in loss of warranty coverage. • An out-of-tune engine, or certain fuel or ignition malfunctions, can cause the catalytic converter to overheat. If you notice a pungent burning odor or some light smoke, your engine may be out of tune or malfunctioning and may require immediate service. Contact your dealer for service assistance. • The use of fuel additives which are now being sold as octane enhancers is not recommended. Most of these products contain high concentrations of methanol. Fuel system damage or vehicle performance problems CAUTION! If the Check Engine or Service Engine Soon light is flashing, immediate service is required. See the On Board Diagnostics paragraph in the Maintenance section of this manual. Materials Added to Fuel All gasoline sold in the United States is required to contain effective detergent additives. Use of additional detergents or other additives is not needed under normal conditions and would result in unnecessary cost. Therefore you should not have to add anything to the fuel.