spark plugs MERCEDES-BENZ ML320 1997 Complete Repair Manual

213 What you should know at the gas station
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Leaving the engine running and the fuel cap open can
cause the “CHECK ENGINE” lamp to illuminate.
Fuel tank capacity approximately 19.0 US gal (72.0 l).
This includes approximately 3.2 US gal (12.0 l) reserve.
Use premium unleaded gasoline: Posted Octane
Index 91 (Average of 96 RON / 86 MON).
•Engine oil
Engine oil level check, see page 89 and page 233.
Fill quantity between upper and lower dipstick
marking level: 2.1 US qt (2.0 l).
Recommended engine oils, see Approved Service
Products sheet.• Coolant
For normal replenishing, use water (potable water
quality).
For further information (e.g. anticorrosion/
antifreeze), see page 292.
• Spark plugs
Approved spark plugs, see page 290.
• Tire pressure
For tire pressure, refer to tire pressure label inside
the fuel filler flap. See page 250 for further details.
• Air conditioner
R-134a refrigerant and special PAG lubricant, see
page 294.
Wa r n i n g !
Overfilling of fuel tank may result in creating
pressure in the system which could cause a gas
discharge such as the gas spraying back out upon
removing the filler nozzle which could cause
personal injury.

290 Technical data
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
Electrical system
We i g h t s
(see certification tag) Model ML 320 ML 430 ML 55 AMG
Generator (alternator) 14 V / 115 A 14 V / 150 A 14 V / 150 A
S t a r te r m o to r 12 V / 1. 7 k W 12V / 1. 7 k W 12V / 1.7 k W
Battery 12V / 100 Ah 12V / 100 Ah 12V / 100 Ah
Spark plugs
Electrode gap
Tightening torqueBosch F 8 DPER
Beru 14 FGH 8 DPUR X 2
0.039 in (1.0 mm)
15–22ft.lb (20–30Nm)Bosch F 8 DPER
Beru 14 FGH 8 DPUR X 2
0.039 in (1.0 mm)
15–22ft.lb (20–30Nm)Bosch F 8 DPER
0.039 in (1.0 mm)
15–22ft.lb (20–30Nm)
Roof load max. 220 lbs (100 kg)

213
What you should know at the gas station
Te ch n ica l
data
Instruments
and controls Operation
Driving Instrument
cluster display Practical hints Car care Index
Leaving the engine running and the fuel cap open can
cause the “CHECK ENGINE” lamp to illuminate.
Fuel tank capacity approximately 19.0 US gal (72.0 l).
This includes approximately 3.2 US gal (12.0 l) reserve.
Use premium unleaded gasoline: Posted Octane
Index 91 (Average of 96 RON / 86 MON).
•Engine oil Engine oil level check, see page 89 and page 233.
Fill quantity between upper and lower dipstick
marking level: 2.1 US qt (2.0 l).
Recommended engine oils, see Approved Service
Products sheet. • Coolant
For normal replenishing, use water (potable water
quality).
For further information (e.g. anticorrosion/
antifreeze), see page 292.
• Spark plugs Approved spark plugs, see page 290.
• Tire pressure For tire pressure, refer to tire pressure label inside
the fuel filler flap. See page 250 for further details.
• Air conditioner R-134a refrigerant and special PAG lubricant, see
page 294.
Wa r n i n g !
Overfilling of fuel tank may result in creating
pressure in the system which could cause a gas
discharge such as the gas spraying back out upon
removing the filler nozzle which could cause
personal injury.

290
Technical data
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints Car care Index
Electrical system
We i g h t s
(see certification tag)
Model ML 320 ML 430 ML 55 AMG
Generator (alternator) 14 V / 115 A 14 V / 150 A 14 V / 150 A
S t a r te r m o to r 12 V / 1. 7 k W 12V / 1. 7 k W 12V / 1.7 k W
Battery 12V / 100 Ah 12V / 100 Ah 12V / 100 Ah
Spark plugs
Electrode gap
Tightening torque Bosch F 8 DPER
Beru 14 FGH 8 DPUR X 2
0.039 in (1.0 mm)
15–22ft.lb (20–30Nm) Bosch F 8 DPER
Beru 14 FGH 8 DPUR X 2
0.039 in (1.0 mm)
15–22ft.lb (20–30Nm) Bosch F 8 DPER
0.039 in (1.0 mm)
15–22ft.lb (20–30Nm)
Roof load max. 220 lbs (100 kg)

297 Technical data
Electrical system
Electrical system
Model
ML 350
ML 500
Generator (alternator)
14 V / 120 A
14 V / 150 A
Starter motor
12 V / 1.7 kW
12 V / 1.7 kW
Battery
12 V / 100 Ah
12 V / 100 Ah
Spark plugs
Bosch F 8 DPP332
Bosch F 8 DPER
Bosch F 8 DPP332
Bosch F 8 DPER
Electrode gap
0.039 in (1.0 mm)
0.039 in (1.0 mm)
Tightening torque
15 – 22 lb-ft (20 – 30 Nm)
15 – 22 lb-ft (20 – 30 Nm)

NOTES ON AVOIDING DAMAGE TO IGNITION SYSTEM - AH15.10-P-0002-01D
Engine 104, 111, 112, 113, 119, 120, 156, 271
To avoid damage to control unit connect and disconnect the two connectors on control unit only when
ignition is switched off.
Terminal 1 of ignition coils must not be short-circuited to GND, e.g. as anti-theft protection.
Install only original ignition system components.
Do not operate ignition system at starting speed unless all of the ignition cables are connected.
No tests such as holding ignition cable 4 at a distance to GND, unplugging a spark plug connector or
pulling cable 4 out of the ignition coils, may be performed at starting speed or when the engine is
running.
Every high voltage circuit must be loaded with at least 2 kohms (spark plug connector).
If it is necessary to test the ignition spark when providing roadside assistance, this must only be done with
a spark plug at a cylinder ignition cable. Ensure that the spark plug has good contact to ground.
Before working at cranking speed, e.g. checking compression pressure, switch off ignition and disconnect
connector "2" from control unit.
Engine 120 has two fuel injection and ignition systems.
Use of testers
Only connect and disconnect secondary measuring sensor to corresponding ignition cables when vertical
engine and ignition are switched off.
If the shot-circuit protection is operated (cylinder comparison) and the engine stays upright, it is not
possible to conduct the test with this test instrument.
Do not connect test lamp to ignition coil terminals 1 and 15.
NOTES ON IGNITION COIL CHARACTERISTICS OF IGNITION SYSTEMS - AH15.10-P-1001-01A
Engine 104, 111, 112, 113, 119, 120

In the case of the twin-spark ignition coil with kV pickup in ignition systems ME-SFI 2.1 and HFM-SFI, no
measurement facilit
y exists at the ignition coil using the kV pickup although a kV pickup is fitted. It is only
damage to ignition system
Notes on avoiding
damage to ignition systemENGINE 104, 111, 112, 113,
119, 120, 156, 271, 112 mit
Benzin-Einspritz- und
Zundsystem MEAH15.10-P-0002-01D
Notes for ceramic glow
plugsENGINE 646.8, 642AH15.20-P-0001-01A

2001 Mercedes-Benz ML320
1998-2005 ENGINE Electrical System - Engine - 163 Chassis
me
Saturday, October 02, 2010 3:18:54 PMPage 2 © 2006 Mitchell Repair Information Company, LLC.

Fig. 3: Diagnosis Test Oscilloscope / Good Image Contactless High Voltage Distribution Primary Side
(Single Image) Engine Idling
BASIC KNOWLEDGE
SPARK PLUGS, LOCATI ON/TASK/DESIGN/FUNCT ION - GF15.10-P-3101F
ENGINE 104, 111, 112, 113/, 119, 120, 137, 166 (except, 112.96, 113.98/99)
Fig. 4: Identifying Spark Plug


2001 Mercedes-Benz ML320
1998-2005 ENGINE Electrical System - Engine - 163 Chassis
me
Saturday, October 02, 2010 3:18:54 PMPage 7 © 2006 Mitchell Repair Information Company, LLC.

IGNITION COILS, LOCATION - GF15.10-P-3102-01A
Fig. 5: Identifying Cylinder 1 To 6 Ignition Coil - Location On Engine 112
Spark plugs, locationOne or two spark plugs are
located in the cylinder head
per cylinder.
Spark plugs, taskThe spark plugs ignite the
suctioned and compressed
fuel-air mixture due to arcing
between the electrodes.
Spark plugs, designIn the manufacturer's specific
type symbols, all the spark
plug features are assigned (e.
g. heat rating, shape of
seating, thread, width across
flats, electrode material,
spark position).
Spark plugs, functionThe ignition voltage travels to
the spark plugs from directly
connected ignition coils or
over the ignition lines from
the ignition coils causing
arcing in the air gap between
the center and ground
electrodes.

2001 Mercedes-Benz ML320
1998-2005 ENGINE Electrical System - Engine - 163 Chassis
me
Saturday, October 02, 2010 3:18:54 PMPage 8 © 2006 Mitchell Repair Information Company, LLC.

Two spark plugs for each cylinder are beneficial because of the arrangement of the valves for achieving optimal
emission levels and smooth engine running.
Each spark plug is actuated separately by the ME-SFI control unit through its own ignition coil. On engine 112,
113 both ignition coils of a cylinder are combined to form a dual ignition coil.
In the lower part load range up to approx. 2000 rpm both ignition sparks of a cylinder are triggered
simultaneously. At moderate and high engine loads, the ignition sparks are triggered offset by as much as 10°
crank angle. In this case, the sequence of actuation is constantly varied in order to achieve a uniform wear of
both spark plugs and to avoid deposits on only one side of the combustion chamber.

For troubleshooting in the dual ignition system, it is possible to switch off one ignition circuit each with HHT or
STAR DIAGNOSIS.
ME-SFI ignition system function
diagramEngine 104GF15.12-P-0001-01D
Engine 111GF15.12-P-0001-01G
Engine 112GF15.12-P-0001-01A
Engine 113GF15.12-P-0001-01B
Engine 119GF15.12-P-0001-01E
Engine 120GF15.12-P-0001-01F
ME-SFI control unit
position/task/design/ function GF07.61-P-5000F
ECI ignition system functionEngine 137GF15.15-P-3000L
Ignition coils,
location/task/design/functionEngine 119, 120GF15.10-P-3102F
Engine 104, 111GF15.10-P-3102G
Engine 112, 113GF15.10-P-3102A
Crankshaft position sensor,
location/task/ design/function GF07.04-P-4116F
Camshaft Hall sensor,
location/task/design/ function GF07.04-P-4117F
Spark plugs,
location/task/design/function GF15.10-P-3101F
Intake air temperature sensor,
location/task/ design/function GF07.04-P-2100F
Hot film mass air flow sensor,
location/task/ design/functionEngine 119, 120 (round
connector)GF07.07-P-4118E
Engine 104, 111, 112,
113, 137GF07.07-P-4118G
Coolant temperature sensor,
location/task/ design/functionEngine 104, 111GF07.04-P-5026G
Engine 112, 113, 137GF07.04-P-5026A
Engine 119, 120GF07.04-P-5026F
Electronic accelerator, Engine 104, 111, 112, GF30.20-P-3010E

2001 Mercedes-Benz ML320
1998-2005 ENGINE Electrical System - Engine - 163 Chassis
me
Saturday, October 02, 2010 3:18:54 PMPage 19 © 2006 Mitchell Repair Information Company, LLC.

version FB6 with code ZS6, -
special protection version FB7
with code ZS7, additional battery
100 Ah incl. cutoff relay code E26.
Model 463.248 with: special
protection version, code 979, -
special protection version FB6,
code ZS6, -special protection
version FB7, code ZS7, -additional
battery 100 Ah including cutoff
relay, code E26.AR54.10-P-0003PM
3.1Unclip cover on front
side of engineModel 211, 215, 220, 230.475/476
4.1Remove engine cover
with integrated air filterExcept model 170.466,
203.065/076/265/276, 209.376/476
from 24.4.04, 211.076/276,
215.374, 220.074/174, 230.474,
463.270/271
The air filter is integrated in the
engine cover. Remove the engine
cover or the air filter housing by
pulling it from the cylinder head
covers vertically in the upward
direction.
4.2Remove air filter housingModel 170.466, 203.065/265,
211.076/276, 215.374,
220.074/174, 230.474AR09.10-P-1150SVK
Model 203.076 /276, 209.376 /476
from 24.4.04, 171.473AR09.10-P-1150AC
Model 463.270/271AR09.10-P-1150GX
5Unscrew screw (5/3) *BA15.10-P-1001-
04A
6Detach spark plug
connector (5/1) from the
spark plugs Pry off spark plug connector
(5/1) using open-end wrench,
double over the cylinder head
cover of the spark plugs.
Installation: Observe the
identification of the connector
(arrow) on the cylinder head cover
and the ignition coil of cylinders 1
to 6 or 1 to 8 for the corresponding
spark plug connector (5/1).
Double open-ended wrenchFig. 24
7Separate electrical
connector of ignition coil
of cylinder 1 to 6 (T1/1 Installation: Install new cable
ties.

2001 Mercedes-Benz ML320
1998-2005 ENGINE Electrical System - Engine - 163 Chassis
me
Saturday, October 02, 2010 3:18:54 PMPage 39 © 2006 Mitchell Repair Information Company, LLC.