1997 Ford Expedition Owner's Manual - Page 169

Maintenance and care How fail-safe cooling works If the engine overheats, the engine will automatically switch from eight to alternating four cylinder operation. Each disabled cylinder acts as an air pump and cools the engine. When this occurs, the engine coolant temperature gauge will move into the red area and the light illuminates. The service engine soon light will illuminate, indicating that vehicle service is required. The vehicle will still operate, but will have limited engine power and no air conditioning capability. Continued operation will increase engine temperature and cause the engine to completely shut down. The vehicle will coast to a stop. As the engine temperature cools, the engine may be re-started. Take your vehicle to a service facility as soon as possible to minimize engine damage. CHECKING AND ADDING POWER STEERING FLUID Check the power steering fluid level at least twice a year. 1. Start the engine. H C 170