2000 SAAB 9-3 octane

136 Starting and drivingUseful tips on cold climate startingIf the engine has failed to start after several
attempts in very cold weather, press and
hold the accelerator down to the floor and
run the starter for 5–10 seconds. This will
prevent the engine being flooded (exces-
sively rich fuel-air mixture).
Now start the engine in the normal way – do
not touch the accelerator.
If the engine stalls immediately after starting
(e.g. if the clutch was released too quickly),
do not touch the accelerator when restarting
the engine.
Every time the engine is switched off the
spark plugs are automatically cleaned. If
your attempt to start nevertheless fails, let
go of the ignition key and allow it to spring
back. This initiates more vigorous cleaning
of the sparking plugs which goes on for
about 5 seconds. Then start in the ordinary
way. Do not touch the accelerator; if the
accelerator is pressed to the floor the fuel
supply is shut off.
Important
considerations for
drivingThe engine-management system in the
Saab 9-3 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 drive-
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 is in the mid-range on tempera-
ture gauge) to avoid unnecessary
wear. If the needle of the pressure
gauge repeatedly enters the red zone
the engine may suddenly lose power,
owing to the intervention of a monitor-
ing system which curtails the charging
pressure. Get in touch with an autho-
rized Saab dealer at once.
 A safety function prevents the engine
from revving faster than 6,200 rpm by
temporarily shutting of the fuel injec-
tors.2 Stopping the engine
 Do not rev the engine immediately
before switching it off - stop the engine
when it is idling.
3 Regulating the charging pressure
 The system is optimized for fuel with an
octane rating of AON 90. For cars with
205 hp engines and the Viggen, the
system is optimized for 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. However, engine perfor-
mance will fall off slightly, and heavy
loading should be avoided. For best
performance you should use the rec-
ommended grade of fuel, AON 90
(205 hp engine and Viggen AON 93).
 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.
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139 Starting and driving
Recommended fuel:The engine in your Saab 9-3 is designed to
operate on unleaded gasoline that has an
octane rating of:
 AON 90 (minimum 87) for 185 hp
engines.
 AON 93 (minimum 87) for 205 hp engines
and Viggen.
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. In many
cases, you may not be able to determine the
exact type or percentage by volume of fuel
additive in the gasoline you purchase for
your car.
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-
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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