Ford 1996 Aerostar Manual page 310

Do not make any unauthorized changes to your
vehicle or engine. Changes that cause more
unburned fuel to reach the exhaust system can
increase the temperature of the engine or
exhaust system.
By law, anyone who manufactures, repairs,
services, sells, leases, trades vehicles, or
supervises a fleet of vehicles is not permitted to
intentionally remove an emission control device
or prevent it from working. In some of the
United States and in Canada, vehicle owners
may be liable if their emission control device is
removed or is prevented from working.
Never use a metal exhaust collector when you
service your vehicle. If the metal collector
contacts any of your vehicle's plastic trim or
bumper parts they could melt or deform.
Do not drive your vehicle if it does not operate
properly. See your dealer if the engine runs on
for more than five seconds after you shut it off
or if it misfires, surges, stalls, or backfires.
Information about your vehicle's emission
control system is on the Vehicle Emission
Control Information decal located on or near the
engine. This decal identifies engine displacement
and gives some tune-up specifications.
Readiness for Inspection/Maintenance
Testing
In some localities it may become a legal
requirement to pass an
Inspection/Maintenance (I/M) test of the
On-Board Diagnostic (OBD) II system. If the
vehicle's powertrain system or its battery has
just been serviced, the OBD II system is reset to
a not ready for I/M testing condition. To
prepare for I/M testing, the law specifies a
"need for additional mixed city and highway
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