Operation Manual

137Starting and driving
Saab 9-3 Viggen: The Saab 9-3 Viggen has
a high-performance engine which means
that a certain amount of care should be
exercised, in particular when accelerating in
the lower gears. This is especially important
when the road surface is slippery to avoid
the driving wheels losing their grip
Important considerations with cata-
lytic converters
The 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 dead), the car
can be push started (manual gearbox
only) or started using jumper cables to a
donor battery. However, as soon as you
have started the engine, it is important
that it runs on all cylinders. If it is misfiring,
allow it to idle for up to five minutes to give
it time to settle and run smoothly. If, after
this time, the engine still fails to run prop-
erly, turn off the engine and get in touch
with an authorized Saab dealer for advice.
• Never park the car on dry grass or other
combustible material. The catalytic con-
verter gets very hot and could therefore
start a fire.
• Never drive off if the engine is misfiring.
• If you jump start the car when the engine
is already up to normal temperature, the
engine must start to run on all cylinders.
NOTE
If 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.
NOTE
If the engine is being run with the car on a
rolling road or dynamometer, longer than
for a standard state emission inspection,
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 corresponding road speed.
NOTE
Use only unleaded gasoline. Leaded gas-
oline is detrimental to the catalyst and
oxygen sensor and will seriously impair
the function of the catalytic converter.
IB1315
Engine-management system with catalytic
converter
1 Engine control module
2 Oxygen sensor (lambda probe)
3 Catalytic converter