low oil pressure MERCEDES-BENZ SLK320 2004 R171 Owner's Manual

180 OperationEngine compartmentBe careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.
Screw filler cap2 back on filler neck.
More information on engine oil can be
found in the “Technical data” section
(
page 277) and (
page 279).
Transmission fluid level
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Center
check the transmission.Coolant
The engine coolant is a mixture of water
and anticorrosion/antifreeze. To check
the coolant level, the vehicle must be
parked on level ground and the engine
must be cool.
The coolant expansion tank is located on
the passenger side of the engine compart-
ment.
!Excess oil must be siphoned or drained
off. It could cause damage to the
engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.
Warning!
G
In order to avoid any possibly serious burns:

Use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system,
or if the coolant temperature gauge indi-
cates that the coolant is overheated.


Do not remove pressure cap on coolant
reservoir if engine temperature is above
194°F (90°C). Allow engine to cool
down before removing cap. The coolant
reservoir contains hot fluid and is under
pressure.


Using a rag, slowly open the cap approx-
imately ½ turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out un-
der pressure.


Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.


186 OperationTires and wheelsLife of tire
The service life of a tire is dependent upon
varying factors including but not limited to:

Driving style


Tire pressure


Distance driven
Direction of rotation
Unidirectional tires offer added advantag-
es, such as better hydroplaning perfor-
mance. To benefit, however, you must
ensure the tires rotate in the direction
specified.
An arrow on the sidewall indicates the in-
tended direction of tire rotation.Checking tire inflation pressureCorrect the tire pressure only when tires
are cold.
Regularly check your tire pressure at inter-
vals of no more than 14 days.
If the tires are warm, you should only cor-
rect the tire pressure if it is too low for cur-
rent operating conditions.
A table on the fuel filler flap lists the spec-
ified tire inflation pressures for warm and
cold tires as well as for various operating
conditions.
Warning!
G
Tires and spare tire should be replaced after
six years, regardless of the remaining tread.!Keep unmounted tires in a cool, dry
place with as little exposure to light as
possible. Protect tires from contact
with oil, grease and gasoline.
Warning!
G
If the tire pressure repeatedly drops:

Check the tires for punctures from for-
eign objects.


Check to see whether air is leaking from
the valves or from around the rim.
iThe pressures listed for light loads are
minimum values offering high driving
comfort.
Increased inflation pressures listed for
heavier loads may also be used for light
loads. These higher pressures produce
favorable handling characteristics. The
ride of the vehicle, however, will be
somewhat harder. Never exceed the
max. values or inflate tires below the
min. values listed in the fuel filler flap.

280 Technical dataFuels, coolants, lubricants etc.Premium unleaded gasoline
Fuel requirements
Use only premium unleaded gasoline
meeting ASTM standard D 439:

The octane number (posted at the
pu mp ) m ust b e 91 m i n. It is an a ve ra ge
of both the Research (R) octane num-
ber and the Motor (M) octane number:
(R+M) / 2). This is also known as the
ANTI-KNOCK INDEX.
Unleaded gasoline containing oxygenates
such as ethanol, IPA, IBA and TBA can be
used provided the ratio of any one of these
oxygenates to gasoline does not exceed
10%; MTBE not to exceed 15%.
The ratio of methanol to gasoline must not
exceed 3% plus additional cosolvents.
Using mixtures of ethanol and methanol is
not allowed. Gasohol, which contains 10%
ethanol and 90% unleaded gasoline, can be
used.
These blends must also meet all other fuel
requirements, such as resistance to spark
knock, boiling range, vapor pressure etc.
Gasoline additives
A major concern among engine manufac-
turers is carbon build-up caused by gaso-
line. Mercedes-Benz recommends only the
use of quality gasoline containing additives
that prevent the build up of carbon depos-
its.
After an extended period of using fuels
without such additives, carbon deposits
can build up especially on the intake valves
and in the combustion area, leading to
engine performance problems such as:

Warm-up hesitation


Unstable idle


Knocking/pinging


Misfire


Power loss
Do not blend any specific fuel additives
with fuel. This only results in unnecessary
costs and may be harmful to engine opera-
tion.
!To maintain the engine’s durability and
performance, premium unleaded gaso-
line must be used. If premium unleaded
is not available and low octane fuel is
used, follow these precautions:

Have the fuel tank only partially
filled with unleaded regular and fill
up with premium unleaded as soon
as possible.


Avoid full throttle driving and abrupt
acceleration.


Do not exceed an engine speed of
3000 rpm if the vehicle is loaded
with a light load such as two per-
sons and no luggage.


Do not exceed
2/3of maximum ac-
celerator pedal position if the vehi-
cle is fully loaded or operating in
mountainous terrain.