Volvo S 90, Owner'S Manual

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STARTING AND DRIVING
375
CAUTION
Avoid spilling gasoline during refueling. In
addition to causing damage to the environ-
ment, gasolines containing alcohol can cause
damage to painted surfaces, which may not
be covered under the New Vehicle Limited
Warranty.
Related information
•
Fuel (p. 372)
•
Octane rating (p. 373)
Emission controls
Three-way catalytic converter
•
Keep your engine properly tuned. Certain
engine malfunctions, particularly involving the
electrical, fuel or distributor ignition systems,
may cause unusually high three-way catalytic
converter temperatures. Do not continue to
operate your vehicle if you detect engine
misfire, noticeable loss of power or other
unusual operating conditions, such as engine
overheating or backfiring. A properly tuned
engine will help avoid malfunctions that
could damage the three-way catalytic con-
verter.
•
Do not park your vehicle over combustible
materials, such as grass or leaves, which can
come into contact with the hot exhaust sys-
tem and cause such materials to ignite under
certain wind and weather conditions.
•
Excessive starter cranking (in excess of one
minute), or an intermittently firing or flooded
engine can cause three-way catalytic con-
verter or exhaust system overheating.
•
Remember that tampering or unauthorized
modifications to the engine, the Engine Con-
trol Module, or the vehicle may be illegal and
can cause three-way catalytic converter or
exhaust system overheating. This includes:
altering fuel injection settings or compo-
nents, altering emission system components
or location or removing components, and/or
repeated use of leaded fuel.
NOTE
Unleaded fuel is required for vehicles with
three-way catalytic converters.
Heated oxygen sensors
The heated oxygen sensors monitor the oxygen
content of the exhaust gases. Readings are fed
into a control module that continuously monitors
engine functions and controls fuel injection. The
ratio of fuel to air into the engine is continuously
adjusted for efficient combustion to help reduce
harmful emissions.
Related information
•
Octane rating (p. 373)