1997 Ford Expedition Owner's Manual - Page 195
1997 Ford Expedition Manual
Page 195 highlights
Maintenance and care Important emission control information By law, anyone who manufacturers, repairs, services, leases, trades vehicles or supervises a fleet of vehicles is not permitted to intentionally remove an emission control device or prevent it from working. Do not make any unauthorized changes to the vehicle or engine. Changes that cause more unburned fuel to reach the exhaust system can increase the temperature of the engine or exhaust system. When your vehicle is serviced, never use a metal exhaust collector. The use of a metal collector may melt or deform plastic parts. Do not park, idle, or drive your vehicle in dry grass or other dry ground cover. The emission system heats up the engine compartment and exhaust system, which can start a fire. Preparing your vehicle for inspection/maintenance (I/M) testing In some localities it may be a legal requirement to pass an I/M test of the on-board diagnostic (OBD II) system. If your vehicle's powertrain system or battery has just been serviced, the OBD II system is reset to a condition unready for I/M testing. To ready the OBD II system for I/M testing, the law 196