2003 Subaru Impreza Owner's Manual - Page 235

Starting and operating D Do not let fuel spill on the exterior surfaces of the vehicle. Fuels may cause paint damage, which is not covered under the SUBARU Limited Warranty. D Always use a genuine SUBARU fuel filler cap. If you use the wrong cap, it may not fit or have proper venting, and your fuel tank and emission control system might be damaged. State emission testing (U.S. only) At state inspection time, remember to tell your inspection or service station in advance not to place your Subaru AWD vehicle on a two-wheel dynamometer. Otherwise, serious transmission damage will result. Some states have started using dynamometers in their state inspection programs in order to meet their obligation under federal law to implement stricter vehicle emission standards to reduce air pollution from cars. A dynamometer is a treadmill or roller-like testing device that allows your car's wheels to turn while the car remains in one place. Depending on the severity of a state's air pollution problems, the states must adopt either a "basic" or "enhanced" vehicle emission inspection test. Normally, a portion of the basic emission test consists of an emission inspector inserting an analyzer probe into the exhaust pipe of an idling vehicle for a short period of time. States with more severe air pollution problems are required to adopt an enhanced vehicle emission test. This test simulates actual driving conditions on a dynamometer and permits more accurate measurement of tailpipe emitted pollution than the basic emission test. The U.S. Environmental Protection Agency (EPA) 7-6