2003 MERCEDES-BENZ C320 COUPE engine

303 Practical hintsFuses
Fuses
Fuse box in passenger compartmentOpening

Pry cover1 open with a screw driver or
similar tool.

Remove cover rearward.
Closing

Attach the cover in the front.

Fold the cover in until it engages.
Fuse chart
The fuse chart is found in the fuse box in
the passenger compartment. The amper-
ages of the fuses are also given there.
Fuse box in engine compartment
The fuse box is located in the engine com-
partment on the left-hand side.
1Cover
2Screw
3Retainer
Removing/installing cover
Twist screws2 90° counterclockwise.

Pull up cover1.

Slide out retainer3 and remove cover
by pulling towards front.

Install cover1 in reverse order.
iOnly install fuses that have been tested
and approved by Mercedes-Benz and
that have the specified amperage rat-
ing.
Never attempt to repair or bridge a
blown fuse. Have the cause determined
and remedied by an authorized
Mercedes-Benz Center.

305 Technical data
Spare parts service
Warranty coverage
Identification labels
Layout of poly-V-belt drive
Engine
Rims and Tires
Electrical system
Main Dimensions
Weights
Fuels, coolants, lubricants etc.
Consumer information

308 Technical dataIdentification labels
Identification labelsCertification label
1Certification label
Vehicle Identification Number (VIN)
2Vehicle Identification Number (VIN)
Identification labels and numbers
3Engine number (engraved on engine)
4VIN, visible (lower edge of windshield)
5Information label, California version
Vacuum line routing for emission con-
trol system
6Emission control label
When ordering spare parts, please specify
vehicle identification and engine numbers.

310 Technical dataEngine
EngineModel
C 230 Kompressor (203.740)
1
1The quoted data apply only to the standard vehicle. See an authorized Mercedes-Benz Center for the corresponding data of all special bodies and special equipment.
C 320 (203.764)
1
Engine
271
112
Mode of operation
4-stroke engine, gasoline injection
4-stroke engine, gasoline injection
No. of cylinders
4
6
Bore
3.23 in (82.00 mm)
3.54 in (89.90 mm)
Stroke
3.35 in (85.00 mm)
3.3 in (84.00 mm)
Total piston displacement
109.6 cu.in. (1796 cm
3)
195.2 cu.in. (3199 cm
3)
Compression ratio
8.5:1
10:1
Output acc. to SAE J 1349
189 hp / 5800 rpm
(141 kW / 5800 rpm)
214 hp / 5700 rpm
(160 kW / 5700 rpm)
Maximum torque acc. to SAE J 1349
192ft.lb/3500rpm
(260 Nm / 3500 rpm)
232ft.lb/3000rpm
(310 Nm / 3000 rpm)
Maximum engine speed
6000 rpm
6000 rpm
Firing order
1-3-4-2
1-4-3-6-2-5
Poly-V-belt
7ft 11in (2420mm)
7 ft 10 in (2390 mm)

317 Technical data
Fuels, coolants, lubricants etc.
Fuels, coolants, lubricants etc.
CapacitiesVehicle components and their respective
lubricants must match. Therefore use only
brands tested and recommended by us. Please refer to the Factory Approved Ser-
vice Products pamphlet, or inquire at your
Mercedes-Benz Center.
Model
Capacity
Fuels, coolants, lubricants etc.
Engine with oil filter
C 230 Kompressor
C320
5.8 US qt (5.5 l)
7.9 US qt (7.5 l)
Recommended engine oils
Automatic transmission
8.5 US qt (8.0 l)
MB Automatic Transmission Oil
1
1MB part no. 001 989 21 03 10Manual transmission
1.3 US qt (1.2 l)
MB Manual Transmission Oil
2
2MB part no. 001 989 26 03 10Rear axle
1.2 US qt (1.1 l)
Hypoid gear oil SAE 85 W 90
Power steering
approx. 1.1 US qt (1.0 l)
MB Power Steering Fluid (Pentosin CHF 11S)
Front wheel hubs
approx. 2.1 oz (60 g) each
High temperature roller bearing grease
Brake system
0.5 US qt (0.5 l)
MB Brake Fluid (DOT 4+)
Cooling system
C 230 Kompressor
C320
approx. 8.5 US qt (8.0 l)
approx. 10.5 US qt (10.0 l)
MB 325.0 Anticorrosion/Antifreeze Agent

319 Technical data
Fuels, coolants, lubricants etc.
Engine oils
Engine oils are specifically tested for their
suitability in our engines. Therefore, use
only engine oils recommended by
Mercedes-Benz. Information on recom-
mended brands is available in the Factory
Approved Service Products pamphlet, or at
your authorized Mercedes-Benz Center.
Please follow FSS recommendations for
scheduled oil changes. Failure to do so
could result in engine damage not covered
by the Mercedes-Benz Limited Warranty.
Engine oil additives
Do not blend oil additives with engine oil.
They may be harmful to the engine opera-
tion.
Damage or malfunctions resulting from
blending oil additives are not covered by
the Mercedes-Benz Limited Warranty.Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG
lubricating oil is used in the air condition-
ing system.
Never use R-12 (CFC) or mineral-based lu-
bricating oil, otherwise damage to the
system will occur.
Brake fluid
During vehicle operation, the boiling point
of the brake fluid is continuously reduced
through the absorption of moisture from
the atmosphere. Under extremely strenu-
ous operating conditions, this moisture
content can lead to the formation of bub-
bles in the system, thus reducing the sys-
tem’s efficiency.
Therefore, the brake fluid must be re-
placed every two years, preferably in the
spring.
Only brake fluid approved by
Mercedes-Benz is recommended. Your au-
thorized Mercedes-Benz Center will pro-
vide you with additional information.

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

The octane number (posted at the
pu mp ) m us t b e 91 mi 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.
!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
2/3 of maximum ac-
celerator pedal position if the vehi-
cle is fully loaded or operating in
mountainous terrain.

321 Technical data
Fuels, coolants, lubricants 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 en-
gine performance problems such as:

Warm-up hesitation


Unstable idle


Knocking/pinging


Misfire


Power lossDo not blend any specific fuel additives
with fuel. This only results in unnecessary
cost and may be harmful to engine opera-
tion.
Damage or malfunctions resulting from
poor fuel quality or from blending specific
fuel additives are not covered by the
Mercedes-Benz Limited Warranty.
Coolants
The engine coolant is a mixture of water
and anticorrosion/antifreeze, which pro-
vides:

Corrosion protection


Freeze protection


Boiling protection (by increasing the
boiling point)
The cooling system was filled at the factory
with a coolant providing freeze protection
to approximately -22°F (-30°C) and corro-
sion protection.
If the antifreeze mixture is effective to
-22°F (-30°C), the boiling point of the cool-
ant in the pressurized cooling system is
reached at approximately 266°F (130°C).
The coolant solution must be used
year-round to provide the necessary corro-
sion protection and increase boil over pro-
tection. You should have it replaced every
15 years or 150 000 miles (250 000 km),
whichever comes first.