Saab 2008 9-5 - Manual (Page 144)

144 Starting and driving
Important
considerations for
driving
The 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
• One of the advantages of boost pres-
sure regulation is that the engine can
also be run safely on gasoline with a
lower octane rating, although not lower
than AON 87. However, engine perfor-
mance will fall slightly and heavy load-
ing and laboring should be avoided. For
optimum performance, use the recom-
mended grade of fuel.
• 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
perfectly 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.
NOTE
• If the engine sounds strange there is a
fault in the system. Have the car
checked without delay by a workshop.
We recommend that you contact an
authorized Saab dealer.
• The use of fuel with too low an octane
rating can cause serious engine
damage.
WARNING
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.
95_US_M08.book Page 144 Friday, May 11, 2007 1:06 PM