2002 SAAB 9-5 octane

149 Starting and driving
Limp-home modeThe car’s engine-management system
includes a diagnostic function that checks
numerous internal functions after the
engine has been shut off. If a fault is
detected in the throttle system, the
engine-management system puts the throt-
tle system into the limp-home mode. This
limits idling control, disables the cruise-con-
trol system and limits the capacity of the A/C
compressor.
If the limp-home mode is in operation
(”Engine malfunction (CHECK ENGINE)”
light on, see below) and the outside temper-
ature is close to or below freezing, you may
need to use some throttle on starting (some
pressure on the accelerator).
If the diagnostic system has detected a fault
in the engine-management system, the
”Engine malfunction (CHECK ENGINE)”
light on the main instrument panel will
come on (see page 53), indicating that you
should have the car checked as soon as
possible by an authorized Saab dealer.
Important
considerations for
drivingThe engine-management system in the
Saab 9-5 is called Saab Trionic T7. The
system manages the ignition, fuel injection
and turbo boost pressure.
The Trionic T7 system developed by Saab
is an intelligent engine-management
system designed to achieve optimum driv-
ability under differing driving conditions.
The system makes adjustments automati-
cally, for instance, if the car is being driven
at altitude (oxygen-deficient air), for differ-
ent grades of fuel (AON 87–93) and for dif-
ferent load conditions.
1 Starting and driving
 Refrain from using full throttle before
the engine has warmed up (before
needle in mid-range on temperature
gauge).
 A safety function prevents the engine
from revving faster than 6,000 rpm by
limiting the induction air.
2 Stopping the engine
 Do not rev the engine immediately
before switching it off - stop the engine
when it is idling.
3 Regulating the boost pressure
 The system is optimized for fuel with an
octane rating of AON 90. The 2.3 T
(Aero) and 3.0t V6 are optimized for
NOTEIf the CHECK ENGINE warning light
starts to flash, ease off the accelerator
slightly. If the light does not cease to flash
within 5 seconds, stop the car in a suita-
ble place as soon as possible and turn off
the engine. The car must be towed to an
authorized Saab dealer.
If the CHECK ENGINE warning light
flashes, it indicates that the engine is
misfiring which can result in damage to
the catalytic converter.
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150 Starting and driving
AON 93. One of the advantages of the
system is that it enables the engine to
be run safely on lower-grade fuel,
although not lower than AON 87.
 The maximum boost pressure is
adjusted automatically to the knocking
or pinging tendency of the engine.
Occasional, short-lived knocking when
the engine is under a heavy load is per-
fectly normal; the extent will depend on
the grade of fuel in the tank.
 Isolated instances of knocking are
more likely to occur with low-octane
fuel. This controlled form of knocking,
followed by a reduction in the boost
pressure, is a sign that the wastegate is
functioning and is perfectly safe for the
engine.
Important considerations with cata-
lytic convertersThe catalytic converter is an emission-con-
trol device incorporated in the car’s exhaust
system. It consists of a metal canister with a
honeycomb insert, the cells of which have
walls coated in a catalytic layer (mixture of
precious metals).
To ensure that the catalytic converter con-
tinues to function properly, and also to avoid
damage to the converter and its associated
components, the following points must be
observed:
 Have the car serviced regularly in accor-
dance with the service program. The fuel
and ignition systems are particularly
important in this context.
 Always be alert to any misfiring of the
engine (not running on all cylinders) and
any loss of power or performance. At the
first sign of a malfunction, reduce speed
and take the car to an authorized Saab
dealer as soon as possible.
 If the engine fails to start (in very cold
weather or if the battery is flat), the car can
be push started (manual gearbox only) or
started using jumper cables to a donor
NOTEIf constant knocking occurs every time a
load is put on the engine, this indicates a
malfunction in the system.
Have the car checked without delay by an
authorized Saab dealer.
WARNING
If the engine is being run with the car on a
rolling road or dynamometer, to ensure
adequate cooling, air must be blown into
the engine compartment and under the
car at a rate equivalent to the ram-air
effect that would be obtained at the corre-
sponding road speed.
NOTEUse only unleaded gasoline. Leaded gas-
oline is detrimental to the catalyst and
oxygen sensor and will seriously impair
the function of the catalytic converter.
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153 Starting and driving
Opening the fuel filler flap in an emergency,
see page 143.
Recommended fuel:The engine in your Saab 9-5 is designed to
operate on unleaded gasoline that has an
octane rating of 87 or higher. Octane rating
is determined according to the formula:
where MON is the Motor Octane Number,
and RON is the Research Octane Number.
The average of these two values is the
octane rating of the gasoline as it appears
on the pump at a retail gas station. This
value is sometimes referred to as the
"Anti-Knock Index" (AKI) or the "Average
Octane Number" (AON).
To avoid deposit formation on the fuel injec-
tors which can cause poor driveability, use
only quality gasolines that contain deter-
gents and corrosion inhibitors. Because
gasolines sold at retail gas stations vary in
their composition and quality, you should
switch to a different brand if you begin expe-
riencing driveability and/or hard starting
problems shortly after refueling your car. In
recent years, a variety of fuel additives and
alcohols or oxygenates have been blended
with gasoline. These types of gasolines may
be found in all parts of the United States and
Canada, but particularly in geographic
areas and cities that have high carbon mon-
oxide levels. Saab approves the use of such
"reformulated" gasolines in its products,
which help in reducing pollution from all
motor vehicles, provided that the following blending percentages are met by such
fuels:
 Up to 10% ethanol by volume, with corro-
sion inhibitors.
 Up to 15% MTBE by volume (methyl ter-
tiary butyl ether).
 Up to 5% methanol by volume, with an
equal amount of a suitable co-solvent and
added corrosion inhibitors.
Other, less common, fuel additives used by
some gasoline dealers are also acceptable,
provided that the resultant gasoline is not
more than 2.7% oxygen by weight.
Some Canadian and U.S. gasolines contain
an octane enhancing additive called meth-
lycyclopentadienyl manganese tricarbonyl
(MMT). If such fuel is used, your emission
control system performance may deterio-
rate and the malfunction indicator lamp on
your instrument panel may turn on. If this
occurs, return to your authorized Saab
dealer for service.
However, these blended gasolines are reg-
ulated and should never exceed these rec-
ommended blend percentages and service
station operators should know if their gaso-
lines contain detergents and oxygenates,
and have been reformulated to reduce vehi-
cle emissions. Nevertheless, if you begin to
notice a problem with the way your car starts
or runs shortly after it has been refueled, try
a different brand of gasoline.
NOTE Fill to maximum filling capacity
 Stop filling after the first time that the
nozzle trips to shut off the flow of fuel
 Filling capacity can differ between
different fuel stations and outside
temperature. Fuel tank volume when
nozzle trips to shut off, may vary by
0.5 gal. (2 liters).
 Do not fill fuel all the way up the filler
pipe. The gasoline must be allowed
room for expansion especially during
hot weather.
MON + RON
2
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154 Starting and driving
Fuel (Gasoline Engine)Use regular unleaded gasoline rated at 87
octane or higher. It is recommended that the
gasoline meet specifications which were
developed by the American Automobile
Manufacturers Association (AAMA) and
endorsed by the Canadian Motor Vehicle
Manufacturers Association for better vehi-
cle performance and engine protection.
Gasolines meeting the AAMA specification
could provide improved driveability and
emission control system performance com-
pared to other gasolines.
NOTEHigher concentrations of methanol than
listed above, or the use of methanol-
blended gasoline without suitable
co-solvents and corrosion inhibitors,
can damage your car’s fuel system,
leading to the need for repairs which are
not covered by Saab’s product warranty.
NOTEThe engine control module (ECM) mon-
itoring the engine parameters also
stores fault codes.
Under certain circumstances, this may
cause constant illumination of the
”Engine malfunction (CHECK
ENGINE)” lamp , thus indicating a
fault that must be checked by your Saab
dealer.
NOTE: always observe the following two
measures:
 Make sure that the fuel filler cap is
screwed on correctly before the
engine is started. Screw on the fuel
filler cap until you hear 3 distinct
clicks.
 Avoid driving with the fuel low level
indicator illuminated. The symbol
illuminates when less than approxi-
mately 2 gallons (8 litres) of fuel
remains in the tank.
In Canada, look for the
”Auto Makers’ Choice” label
on the fuel pump.
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155 Starting and driving
Canada Only
Be sure the posted octane is at least 87. If
the octane is less than 87, you may get a
heavy knocking noise when you drive. If it’s
bad enough, it can damage your engine. If
you’re using fuel rated at 87 octane or
higher and you hear heavy knocking, your
engine needs service. But don’t worry if you
hear a little pinging noise when you’re accel-
erating or driving up a hill. That’s normal,
and you don’t have to buy a higher octane
fuel to get rid of pinging. It’s the heavy, con-
stant knock that means you have a problem.
If your vehicle is certified to meet California
Emission Standards (indicated on the
underhood emission control label), it is
designed to operate on fuels that meet Cal-
ifornia specifications. If such fuels are not
available in states adopting California emis-
sions standards, your vehicle will operate
satisfactorily on fuels meeting federal spec-
ifications, but emission control system per-
formance may be affected. The ”Engine
malfunction (CHECK ENGINE)” indicator
on your main instrument panel may turn on
and/or your vehicle may fail a smog-check
test. See ”Engine malfunction (CHECK
ENGINE)” indicator on page 53. If this
occurs, return to your authorized Saab
dealer for diagnosis to determine the cause
of failure. In the event it is determined that
the cause of the condition is the type of fuels
used, repairs may not be covered by your
warranty. Some gasolines that are not reformulated
for low emissions may contain an
octane-enhancing additive called methylcy-
clopentadienyl manganese tricarbonyl
(MMT); ask your service station operator
whether or not the fuel contains MMT. Saab
Automobile AB does not recommend the
use of such gasolines. If fuels containing
MMT are used, spark plug life may be
reduced and your emission control system
performance may be affected. The malfunc-
tion indicator lamp on your instrument panel
may turn on. If this occurs, return to your
authorized Saab dealer for service.
Engine Break-In PeriodPistons, bores and bearings need time to
obtain uniform, wear-resistant surfaces.
If a new engine is driven too hard, this grad-
ual process of bedding-in will not be possi-
ble and the life of the engine will be short-
ened.
During the first 1,200 miles (2,000 km), do
not exceed 5,000 rpm.
In addition, refrain from driving the car at full
throttle, other than for brief instances,
during the first 1,800 miles (3,000 km). Wearing in new brake padsNew brake pads take time to bed in, about
90 miles (150 km) if the car is driven largely
under stop-and-go conditions or about
300 miles (500 km) of highway driving.
To extend the useful life of the pads, avoid
hard braking as much as possible during
this period.
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