1998 Toyota Sienna Owners Manual - Page 104

name. SIENNA (U) Engine coolant temperature gauge The gauge indicates the engine coolant temperature when the ignition switch is on. The engine operating temperature will vary with changes in weather and engine load. If the needle moves into the red zone, your engine is too hot. If your vehicle overheats, stop your vehicle and allow the engine to cool. Your vehicle may overheat during severe operating conditions, such as: With tachometer NOTICE z Do not remove the thermostat in the engine cooling system as this may cause the engine to overheat. The thermostat is designed to control the flow of coolant to keep the temperature of the engine within the specified operating range. z Do not continue driving with an overheated engine. See "If your vehicle overheats" in Part 4. D Driving up a long hill on a hot day. D Reducing speed or stopping after high speed driving. D Idling for a long period with the air conditioning on in stop−and−go traffic. D Towing a trailer. Without tachometer 104