2004 Dodge Dakota Owner's Manual - Page 186
2004 Dodge Dakota Manual
Page 186 highlights
186 STARTING AND OPERATING sulfur to determine if the problem is fuel related prior to returning your vehicle to an authorized dealer for service. ADDING FUEL Fuel Filler Cap (Gas Cap) The gas cap is behind the fuel filler door. If the gas cap is lost or damaged, be sure the replacement cap is for use with this vehicle. CAUTION! If the Check Engine or Service Engine Soon light is flashing, immediate service is required; see onboard diagnostics system section. Materials Added To Fuel All gasolines sold in the United States are 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. CAUTION! Damage to the fuel system or emission control system could result from using an improper fuel tank filler tube cap (gas cap). A poorly fitting cap could let impurities into the fuel system.