2003 Ford Excursion Diesel Supplement 2nd Printing - Page 9
2003 Ford Excursion Manual
Page 9 highlights
Warning lights Do not drain the HFCM while the engine is running. Fuel may ignite if the separator is drained while the engine is running or the vehicle is moving. ENGINE AIR FILTER The engine air filter warning light illuminates when the air filter restriction gauge reaches the CHANGE FILTER mark. The condition should be verified by inspecting the underhood air filter restriction gauge; the warning light is only a secondary indicator. Always use the underhood air filter restriction gauge to determine when the air filter element needs to be changed The vehicle may be driven with the engine air filter warning light illuminated/or when the underhood air filter restriction gauge has moved to the CHANGE FILTER mark for up to 400 km (250 miles) without damaging the engine or related components. However, the air filter element must be replaced at the earliest opportunity. Refer to Air filter restriction gauge in the Diesel information chapter for more information. 9