Saab 1987 900 - Turbo Model Special Instructions

sion). Cars with automatic transmis-
sions can only be started when the gear
selector lever is in P or N.
2 Fully depress the
clutch pedal (manual
transmission) .
3
Turn the key to the start position and let
it spring back as soon as the engine has
started. Allow the engine to idle for
about 10 seconds before touching the
accelerator. Do not depress the ac-
celerator for full throttle until the en-
gine
has run for at least 2-3 minutes.
Ifthe engine stalls immediately after start-
ing in cold weather, keep the accelerator
depressed while at the same time running
the starter for a few seconds, to ensure that
the fuel/air mixture is not too rich.
NOTE! 16 valve engines have hydraulic
valve lifters
which require no service. The
clearances are pre-set when the engine is
assembled and no adjustments are
necessary. Some valve lifter noise may be
heard for a few seconds after the engine
has been started, and this should be con -
sidered normal. The valve noise will
disappear once the engine oil has reac-
hed normal working pressure.
For
restarting a warm engine when the out-
side
temperature is high, depressing the
accelerator during cranking may assist
start up.
NOTE! Saab 900 Turbo:
STARTING-Don't rev
the engine imme-
diately after starting or permanent
damage to the turbocharger will result.
STOPPING-Let the engine idle 20-30
seconds before switching it off after dri-
ving to
allow time for the turbocharger to
coast
down from high rpm before oil
pressure
at the bearing is depleted. For
the same reason, don't rev the engine
immediately before switching ifoff. Per -
manent turbocharger damage will
result.
After
hard driving let the engine idle about
a minute to let the oil cool the turbocharger
bearings somewhat. This will also help pre-
vent
breakdown of the oil. If the engine is
very
hot, the radiator fan may cut in and
continue to run for a while after the engine
has been switched off.
Special instructions -
Turbo
models
General information, turbochargers
The turbocharger is what really makes the
Saab Turbo special, being the component
that harnesses what is normally wasted
heat energy in the exhaust. It has a precision
made and balanced turbine wheel/com-
pressor impeller assembly capable ofvibra -
tion free
operation at tellS of thousands of
revolutions per minute.
Starting and driving 31
The impeller shaft bearings actually floats
on a thin film of engine oil circulated
through the turbocharger housing by the
engine oil pump. The turbocharger will last
the life ofthe car provided that it is not run
without oil pressure at the bearing, the
engine oil and filter change requirements
are fulfilled, and no foreign objects pass
through either the turbine or compressor
side. The unit is sealed and should never be
disassembled or cleaned internally.
APe system benefits
The APC System detects the onset of engine
knock and adjusts the charging pressure of
the turbocharged engine accordingly. With
the engine thus protected from excessive
and potentially harmful knock, the com -
pression
ratio was able to be increased to
improve overall fuel efficiency.
The capability of the APC system to con -
stantly adjust maximum charging pressure
for variance of fuel octane and engine ope -
rating conditions allows optimum perfor-
mance to be obtained relative to the fuel
quality chosen. Using 92 octane (pump
rating) fuel, little or no knocking will be
heard and maximum performance will be
available. On 87 octane, audible knock will
be present (but controlled) under load and
performance will be somewhat reduced
due to the effect ofthe APC system upon the
maximum charging pressure.
The APC system calibration provided on the
Turbo with the Special Performance Group