2000 Lexus RX 300 Owners Manual - Page 443

ENGINE If your engine knocks ...If you detect heavy knocking even when using the recommended fuel, or if you hear steady knocking while holding a steady speed on level roads, consult your Lexus dealer. However, now and then, you may notice light knocking for a short time while accelerating or driving up hills. This is no cause for concern. Cleaner burning gasoline Cleaner burning gasoline, including reformulated gasoline that contains oxygenates such as ethanol or MTBE is available in many areas. Lexus recommends the use of cleaner burning gasoline and appropriately blended reformulated gasoline. These types of gasoline provide excellent vehicle performance, reduce vehicle emissions, and improve air quality. Gasoline containing detergent additives Lexus recommends the use of gasoline that contains detergent additives to avoid build-up of engine deposits. However, all gasoline sold in the U.S. contains detergent additives to keep clean and/or clean intake systems. Oxygenates in gasoline Lexus allows the use of oxygenate blended gasoline where the oxygenate content is up to 10% ethanol or 15% MTBE. If you use gasohol in your Lexus, be sure that it has an octane rating no lower than 87. Lexus does not recommend the use of gasoline containing methanol. Quality gasoline Automotive manufacturers in the U.S., Europe and Japan have developed a specification for quality fuel named World-Wide Fuel Charter (WWFC) that is expected to be applied world wide. The WWFC consists of three categories that depend on required emission levels. In the U.S., category 3 has been adopted. The WWFC improves air quality by providing for better emissions in vehicle fleets, and customer satisfaction through better vehicle performance. 426 Sulfur in gasoline If your vehicle is certified to California Emission Regulation, the vehicle is designed to operate on California cleaner burning gasoline (CBG) that contains lower sulfur. If you cannot use California CBG, your emission control system may suffer damage and turn on the Malfunction Indicator Lamp. If the malfunction is caused by the type of fuel used, repairs may not be covered by your warranty.