Illumination of the service engine soon
indicator, charging system warning light or
the temperature warning light, fluid leaks,
strange odors, smoke or loss of engine
power could indicate that the emission
control system is not working properly.
An improperly operating or damaged
exhaust system may allow exhaust to
enter the vehicle. Have a damaged or
improperly operating exhaust system
inspected and repaired immediately.
Do not make any unauthorized changes to
your vehicle or engine. By law, vehicle
owners and anyone who manufactures,
repairs, services, sells, leases, trades
vehicles, or supervises a fleet of vehicles
are not permitted to intentionally remove
an emission control device or prevent it
from working. Information about your
vehicle’s emission system is on the Vehicle
Emission Control Information Decal
located on or near the engine. This decal
also lists engine displacement.
Please consult your warranty information
for complete details.
On-Board Diagnostics (OBD-II)
Your vehicle has a computer known as the
on-board diagnostics system (OBD-II) that
monitors the engine’s emission control
system. The system protects the
environment by making sure that your
vehicle continues to meet government
emission standards. The OBD-II system
also assists a service technician in properly
servicing your vehicle.
When the service engine soon
indicator illuminates, the OBD-II
system has detected a
malfunction. Temporary malfunctions may
cause the service engine soon indicator to
illuminate. Examples are:1. Your vehicle has run out of fuel—the
engine may misfire or run poorly.
2. Poor fuel quality or water in the
fuel—the engine may misfire or run
poorly.
3. The fuel fill inlet may not have closed
properly. See Refueling (page 110).
4. Driving through deep water—the
electrical system may be wet.
You can correct these temporary
malfunctions by filling the fuel tank with
good quality fuel, properly closing the fuel
fill inlet or letting the electrical system dry
out. After three driving cycles without these
or any other temporary malfunctions
present, the service engine soon indicator
should stay off the next time you start the
engine. A driving cycle consists of a cold
engine startup followed by mixed city and
highway driving. No additional vehicle
service is required.
If the service engine soon indicator remains
on, have your vehicle serviced at the first
available opportunity. Although some
malfunctions detected by the OBD-II may
not have symptoms that are apparent,
continued driving with the service engine
soon indicator on can result in increased
emissions, lower fuel economy, reduced
engine and transmission smoothness and
lead to more costly repairs.
Readiness for Inspection and
Maintenance (I/M) Testing
Some state and provincial and local
governments may have
Inspection/Maintenance (I/M) programs
to inspect the emission control equipment
on your vehicle. Failure to pass this
inspection could prevent you from getting
a vehicle registration.
If the service engine soon
indicator is on or the bulb does
not work, your vehicle may need
service. See On-Board Diagnostics.
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Engine Emission Control
