1999 Lexus SC 400 Owners Manual - Page 357

ENGINE Gasolines quality In a very few cases, you may experience driveability problems caused by the particular gasoline that you are using. If you continue to have unacceptable driveability, try changing gasoline brands. If that does not rectify your problem, then consult your Lexus dealer. FACTS ABOUT ENGINE OIL CONSUMPTION Functions of engine oil Engine oil has the primary function of lubricating and cooling the inside of the engine, and plays a major role in maintaining the engine in proper working order. NOTICE D Do not use gasohol other than stated above. It will cause fuel system damage or vehicle performance problems. D If drivability problems are encountered (poor hot starting, vaporizing, engine knock, etc.), discontinue its use. D Take care not to spill gasohol during refueling. Gasohol may cause paint damage. Engine oil consumption It is normal that an engine should consume some engine oil during normal engine operation. The causes of oil consumption in a normal engine are as follows. D Oil is used to lubricate pistons, piston rings and cylinders. A thin film of oil is left on the cylinder wall when a piston moves downwards in the cylinder. High negative pressure generated when the vehicle is decelerating sucks some of this oil into the combustion chamber. This oil as well as some part of the oil film left on the cylinder wall is burned by the high temperature combustion gases during the combustion process. D Oil is also used to lubricate the stems of the intake valves. Some of this oil is sucked into the combustion chamber together with the intake air and is burned along with the fuel. High temperature exhaust gases also burn the oil used to lubricate the exhaust valve stems. Fuel tank capacity 78 L (20.6 gal., 17.2 lmp.gal.) 339