MERCEDES-BENZ SPRINTER 2006 Service Manual

FUEL DRAIN TUBES
DIAGNOSIS AND TESTING - FUEL SUPPLY
RESTRICTIONS
LOW - PRESSURE LINES
Fuel supply line restrictions can cause starting
problems and prevent engine from accelerating. The
starting problems include; low power and/or white
fog like exhaust.
Test all fuel supply lines for restrictions or block-
age. Flush or replace as necessary.
HIGH - PRESSURE LINES
CAUTION: High pressure lines cannot contact each
other or other components. Do not attempt to weld
high-pressure fuel lines or to repair lines that are
damaged. High pressure lines must be replaced at
each disassembly. Use only recommended lines
when replacement of high-pressure fuel line is nec-
essary.
Restricted (kinked or bent) high-pressure lines can
cause starting problems, poor engine performance,engine mis-fire and white smoke from exhaust (Refer
to 14 - FUEL SYSTEM - WARNING).
FUEL FILTER
DESCRIPTION
The fuel filter was designed for improved high alti-
tude operation and for better re-start after the fuel
tank has been completely emptied. The water drain
plug and water in fuel (WIF) sensor are located on
the top of the filter. Water is drained by using the in-
tank electric fuel pump to generate flow (attach a
hose to the drain plug). The filter has a pressure dif-
ferential of 200±300 mbar (2.9 psi.) when new. When
dirty, the pressure differential rises to 800 mbar (11.6
psi.) (Fig. 2).
REMOVAL
WARNING: NO SPARKS, OPEN FLAMES OR SMOK-
ING. RISK OF POISONING FROM INHALING AND
SWALLOWING FUEL. RISK OF INJURY TO EYES
AND SKIN FROM CONTACT WITH FUEL. POUR
FUELS ONLY INTO SUITABLE AND APPROPRI-
ATELY MARKED CONTAINERS. WEAR PROTECTIVE
CLOTHING.
CAUTION: DO NOT bend, twist or cut the fuel hose
clamps. The fuel hose clamps through out the fuel
system are reusable when using special tool #9539.
Orginal clamps must be used when servicing the
fuel system.
(1) Disconnect negative battery cable.
(2) Disconnect the water in fuel (WIF) sensor har-
ness connector (Fig. 2).
(3) Release the fuel inlet and outlet hose clamps
using special tool #9539 at the fuel filter (Fig. 2).
(4) Remove fuel filter retaining bracket bolt and
remove fuel filter (Fig. 2).
(5) Separate the WIF sensor from the fuel filter
(Fig. 2)
FUEL LINE WRENCH-9285
FUEL LINE PLIERS-9539
14 - 10 FUEL DELIVERYVA

INSTALLATION
WARNING: NO SPARKS, OPEN FLAMES OR SMOK-
ING. RISK OF POISONING FROM INHALING AND
SWALLOWING FUEL. RISK OF INJURY TO EYES
AND SKIN FROM CONTACT WITH FUEL. POUR
FUELS ONLY INTO SUITABLE AND APPROPRI-
ATELY MARKED CONTAINERS. WEAR PROTECTIVE
CLOTHING.
CAUTION: DO NOT bend, twist or cut the fuel hose
clamps. The fuel hose clamps through out the fuel
system are reusable when using special tool #9539.
Orginal clamps must be used when servicing the
fuel system.
NOTE: Capture any fuel spillage and dispose of in
appropriately marked container.
(1) Fill new fuel filter with the new diesel fuel
(approximately 0.4 liters)
(2) Carefully seat WIF sensor and tighten bolt to
13 lbs. in. (1.5 N´m) (Fig. 2)
(3) Position fuel filter in bracket and tighten
retaining bolt to 53 lbs. in. (6 N´m) (Fig. 2)
(4) Install fuel lines and re-crimp clamps using
special tool #9539 (Fig. 2).
(5) Connect the WIF wiring harness connector
(Fig. 2).
(6) Connect negative battery cable.(7) Cycle ignition several times to build pressure.
(8) Start engine and inspect for leaks.
FUEL LINES
REMOVAL - HIGH PRESSURE LINES
WARNING: NO SPARKS, OPEN FLAMES OR SMOK-
ING. RISK OF POISONING FROM INHALING AND
SWALLOWING FUEL. RISK OF INJURY TO EYES
AND SKIN FROM CONTACT WITH FUEL. POUR
FUELS ONLY INTO SUITABLE AND APPROPRI-
ATELY MARKED CONTAINERS. WEAR PROTECTIVE
CLOTHING.
(1) Disconnect negative battery cable.
CAUTION: Counterhold with wrench at threaded
connections of injectors. DO NOT EXCEED the
tightening torque in order to avoid also slackings
the threaded connection.
CAUTION: DO NOT crimp or bend lines.
NOTE: After removing injection lines, seal connec-
tions and ensure cleanliness.
(2) Unscrew union nuts of injection lines.
(3) Remove injection lines (Fig. 3).
Fig. 2 FUEL FILTER
1 - FUEL SUPPLY LINE TO HIGH PRESSURE PUMP
2 - FUEL FILTER
3 - WIF SENSOR
4 - FUEL FILTER DRAIN
VAFUEL DELIVERY 14 - 11

INSTALLATION - HIGH PRESSURE LINES
WARNING: NO SPARKS, OPEN FLAMES OR SMOK-
ING. RISK OF POISONING FROM INHALING AND
SWALLOWING FUEL. RISK OF INJURY TO EYES
AND SKIN FROM CONTACT WITH FUEL. POUR
FUELS ONLY INTO SUITABLE AND APPROPRI-
ATELY MARKED CONTAINERS. WEAR PROTECTIVE
CLOTHING.
(1) Loosen the fuel rail mounting bolts to install
lines free of stress.
CAUTION: Inspect sealing cone at lines. Replace if
compression points exist. Ensure lines are exactly
located.
(2) Position and install fuel lines (Fig. 3). Tighten
to 22N´m (195 lbs. in.) using a wrench to counterhold
at threaded connection.
(3) Tighten fuel rail to 14N´m (124 lbs. in.).
(4) Connect negative battery cable.
CAUTION: Care must be taken when installing the
engine cover. Assure the proper routing of the fuel
injector return fuel hose to the banjo bolt fitting in
the left rear corner of the cover. Failure to do so
may pinch or damage the hose causing fuel leakage
or a driveability concern.(5) Start engine, run for a few minutes, turn
engine off and inspect for leaks (Refer to 14 - FUEL
SYSTEM - WARNING), (Refer to 14 - FUEL SYS-
TEM - DIAGNOSIS AND TESTING).
FUEL RAIL PRESSURE SEN-
SOR
DESCRIPTION
The fuel rail pressure sensor is attached to the
front of the fuel rail. The sensor supplies the current
fuel rail pressure to the ECM.
OPERATION
Non-constant fuel system pressure influences the
position of a diaphragm inside the sensor. This
results in a variation in the electrical resistance. The
fuel rail pressure sensor supplies the appropriate
voltage signal to the ECM.
REMOVAL
(1) Disconnect the negative battery cable.
(2) Disconnect the sensor wiring harness connector
(Fig. 4).
NOTE: Place a shop towel underneath the sensor to
capture any fuel spillage.
(3) Unscrew the sensor and discard the seal.
Fig. 3 FUEL RAIL
1 - CAMSHAFT POSITION SENSOR
2 - FUEL INJECTOR
3 - FUEL INJECTOR VALLEY DRAIN
4 - FUEL RAIL PRESSURE CONTROL VALVE
5 - BANJO BOLT
6 - FUEL RAIL
7 - HIGH PRESSURE FUEL LINE
Fig. 4 FUEL RAIL PRESSURE SENSOR
1 - FUEL RAIL PRESSURE SENSOR
2 - FUEL RAIL
3 - COOLANT TEMPERATURE SENSOR
14 - 12 FUEL DELIVERYVA

INSTALLATION
(1) Install the sealing ring onto the sensor and
screw the fuel pressure sensor into the fuel rail.
(2) Tighten the senor to 60 N´m (44 ft. lbs.), back
it off 90 degrees and retighten to 80 N´m (59 ft. lbs.)
(Fig. 4).
(3) Connect the sensor wiring harness connector.
CAUTION: Care must be taken when installing the
engine cover. Assure the proper routing of the fuel
injector return fuel hose to the banjo bolt fitting in
the left rear corner of the cover. Failure to do so
may pinch or damage the hose causing fuel leakage
or a driveability concern.
(4) (Refer to 14 - FUEL SYSTEM - WARNING).
Start engine, allow to run for a few minutes, turn the
engine off and inspect for leaks.
FUEL PUMP
DESCRIPTION
DESCRIPTION - HIGH PRESSURE PUMP
WARNING: (Refer to 14 - FUEL SYSTEM - WARN-
ING)
The high pressure pump is a fuel regulated radial
piston pump with three pistons arranged at an angle
of 120É. The regulation being carried out by the fuel
quantity valve. The high pressure pump is driven at
about 1.3 times the speed of the camshaft. Specific
moving parts inside the pump are graphite coated to
assist with the lubrication process during operation.
The high pressure pump is mounted to the front of
the cylinder head and must be replaced as an assem-
bly should a failure occur (Fig. 5).
DESCRIPTION - LOW PRESSURE PUMP
The electric fuel pump is located in the fuel tank.
The pump draws warm or hot fuel from the fuel tank
module bowl and also draws cool fuel out of the tank.
The cool fuel is drawn in and is mixed with the fuel
already in the bowl in a 50±50 mix ratio. Refer to
fuel pump module for servicing (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/FUEL TANK MODULE
- REMOVAL).
OPERATION
OPERATION
LOW PRESSURE SIDE
The fuel supplied by the low pressure pump flows
through the fuel supply (5) at the high pressure
pump and is passed to the fuel quantity valve (11)
and the fuel pressure relief valve (9). Any air
entrained by the fuel is directed through the restric-
tor (10) through the bleed port (7) to the return flow
(6). The quantity control valve (11) controls the
amount of fuel that flows along the ring passage (4)
through the supply ports to the three high pressure
pump elements. To lubricate the plunger and barrel
assemblies when the quantity control valve is closed
Fig. 5 HIGH PRESSURE FUEL PUMP
1 - HIGH PRESSURE PUMP
2 - FUEL SUPPY TO FUEL RAIL
3 - FUEL SUPPLY LINE
4 - FUEL RETURN LINE
5 - FUEL TEMPERATURE SENSOR
6 - FUEL QUANTITY CONTROL VALVE
7 - OIL LEVEL INDICATOR
8 - VACUUM PUMP
VAFUEL DELIVERY 14 - 13

(over run mode), the fuel is led directly to the circu-
lar port by the zero delivery restrictor (10) (Fig. 6).
The fuel pressure relief valve (9) limits the fuel
pressure which exists at the fuel quantity control
valve (11) to approximately 5 bar (72.5 psi). If the
pressure is exceeded, the pressure relief valve opens
and passes the fuel to the return flow (6) (Fig. 6).
The fuel pressure relief valve (9) directs a portion
of the fuel as a lubricant to the eccentric shaft (8)
(Fig. 6).
14 - 14 FUEL DELIVERYVA

HIGH PRESSURE SIDE
A. Filling the piston:The piston (6) is moved
down as a result of the piston spring (7). The fuel
supplied by the fuel delivery pump flows along the
ring passage (10), the valve disk and the valve spring
(3) into the cylinder. The check ball (4) prevents the
fuel from being able to flow back from the high pres-
sure passage (5) (Fig. 7).
B. Producing high pressure:The piston (6) is
moved up by the rising eccentric shaft (9) and the
fuel is compressed. The valve (2) disk shuts off the
delivery volume to the fuel supply. Once the fuel
pressure in the cylinder rises beyond the pressure
which exists in the high pressure circuit (5), the
check ball (4) opens and the fuel is pumped into the
high pressure circuit (5) (Fig. 7).
Fig. 6 LOW PRESSURE SIDE
1 - HIGH PRESSURE PUMP 7 - FUEL BLEED PORT
2 - FUEL TEMPERATURE SENSOR 8 - SHAFT LUBRACATION PORT
3 - FUEL SUPPLY TO PUMP ELEMENTS 9 - FUEL PRESSURE RELIEF VALVE
4 - FUEL ANNULAR PORT 10 - ZERO DELIVERY RESTRICTOR
5 - FUEL SUPPLY 11- FUEL QUANTITY VALVE
6 - FUEL RETURN
VAFUEL DELIVERY 14 - 15

OPERATION - LOW PRESSURE PUMP
When the ignition switch is on, fused battery posi-
tive voltage is supplied to the electric lift pump,
which will run for 20±30 seconds and then stop. If
the engine is cranked, the pump will begin running
immediately supplying fuel through fuel filter and
onto the high pressure pump. The lift pump and low
pressure fuel circuit operate at a pressure between
3.8 -5.5 bar (55 - 80 psi.).
Fig. 7 PRODUCING HIGH PRESSURE
1 - FUEL SUPPLY TO PUMP 6 - PISTON
2 - VALVE 7 - PISTON SPRING
3 - VALVE SPRING 8 - CAM
4 - CHECK BALL 9 - ECCENTRIC SHAFT
5 - HIGH PRESSURE PASSAGE 10 - CIRCULAR PASSAGE
14 - 16 FUEL DELIVERYVA

REMOVAL - HIGH PRESSURE PUMP
(Refer to 14 - FUEL SYSTEM - WARNING)
(1) Disconnect negative battery cable.
(2) Remove viscous fan clutch (Refer to 7 - COOL-
ING/ENGINE/FAN DRIVE VISCOUS CLUTCH -
REMOVAL).
(3) Unplug electrical connectors at high pressure
pump.
CAUTION: DO NOT slacken the threaded connec-
tion. Use a wrench to counterhold at the threaded
connection when loosening and tightening the
union nut. DO NOT EXCEED tightening torque.
CAUTION: DO NOT crimp or bend fuel line. Capture
all fluids that flow out of connections.
(4) Disconnect the high pressure line at high pres-
sure pump (Fig. 8).
(5) Detach fuel supply and return flow line at high
pressure pump using special tool #9539 (Fig. 8).
NOTE: Care must be taken not to drop the high
pressure pump drive when removing pump. Inspect
the pump drive for wear. If wear is present replace
the drive and gear.(6) Remove bolts attaching high pressure pump
and remove pump (Fig. 8).
INSTALLATION - HIGH PRESSURE PUMP
(Refer to 14 - FUEL SYSTEM - WARNING)
CAUTION: Clean sealing surfaces with appropriate
solvents and replace all seals.
NOTE: Inspect then attach high pressure pump
drive if pump is being replaced. If wear is present at
drive, replace drive and gear.
(1) Position and secure the high pressure pump to
cylinder head (Fig. 9). Tighten bolts to 14 N´m (124
lbs. in.).
CAUTION: NEVER slacken the thread connection.
Use a wrench to counterhold at threaded connec-
tion when slackening and tightening torque in order
to avoid also slackening the threaded connection
the next time.
Fig. 8 HIGH PRESSURE FUEL PUMP
1 - INTERMEDIATE GEAR
2 - HIGH PRESSURE PUMP
3 - SEALING RING
4 - DRIVER
5 - HIGH PRESSURE LINE
6 - FUEL SUPPLY LINE
7 - FUEL RETURN LINE
8 - BOLTS
9 - FUEL QUANTITY CONTROL VALVE
10 - FUEL TEMPERATURE SENSOR
Fig. 9 HIGH PRESSURE FUEL PUMP
1 - INTERMEDIATE GEAR
2 - HIGH PRESSURE PUMP
3 - SEALING RING
4 - DRIVER
5 - HIGH PRESSURE LINE
6 - FUEL SUPPLY LINE
7 - FUEL RETURN LINE
8 - BOLTS
9 - FUEL QUANTITY CONTROL VALVE
10 - FUEL TEMPERATURE SENSOR
VAFUEL DELIVERY 14 - 17

CAUTION: DO NOT crimp or bend fuel line. Inspect
sealing cone at line; replace line if compression
exists.
NOTE: Care must be taken not to cross the fuel
return and supply lines during installation.
(2) Attach fuel flow supply and return lines,
recrimping clamps using special tool #9539 (Fig. 9).
CAUTION: NEVER slacken the thread connection.
Use a wrench to counterhold at threaded connec-
tion when slackening and tightening torque in order
to avoid also slackening the threaded connection
the next time.
CAUTION: DO NOT crimp or bend fuel line. Inspect
sealing cone at line; replace line if compression
exists.
(3) Attach high pressure fuel line to pump.
Tighten to 22N´m (194 lbs.in.) (Fig. 9).
(4) Install the viscous fan.
(5) Connect negative battery cable.
(6) Start engine, allow to run, turn engine off and
inspect for leaks (Refer to 14 - FUEL SYSTEM -
WARNING), (Refer to 14 - FUEL SYSTEM - DIAG-
NOSIS AND TESTING).
FUEL PUMP MODULE
DESCRIPTION
The fuel pump module is installed in the top of the
fuel tank (Fig. 10). The pump module contains the
following components:
²Electric fuel pump (transfer, or lift pump)
²Fuel reservoir
²Fuel gauge sending unit (fuel level sensor)
²Fuel supply line connection
²Fuel return line connectionFuel is supplied to the high-pressure fuel injection
pump by the low-pressure fuel transfer (lift) pump.
This electric fuel pump is attached to the fuel pump
module and supplies approximately 165 liters/hour
(43.6 gallons/hour). A low-pressure fuel pump is not
attached to the engine.
REMOVAL
CAUTION: To prevent damage to the float rod, the
float and float rod must be removed from the pump
module. This step must be done before the pump
module is removed from the fuel tank.
(1) Drain and remove fuel tank. Refer to Fuel
Tank Removal/Installation.
(2) Thoroughly clean area around pump module at
top of tank.
(3) Disconnect all fuel lines from pump module fit-
tings.
(4) The plastic fuel pump module locknut (lock-
ring) is threaded onto fuel tank. Install Special Tool
#6856 to locknut and remove locknut (Fig. 11). The
fuel pump module will spring up slightly after lock-
nut is removed.
Fig. 10 TOP OF FUEL TANK
1 - Cooler Lines
2-TopofTank
3 - Expansion Tank
4 - Check Valves
5 - Check Valve
6 - Module Lock Ring
7 - Fuel Pump Module
14 - 18 FUEL DELIVERYVA

(5) Pull module assembly up just a few inches to
gain access to float support arm/rod (3) (Fig. 12). Be
careful not to bend float support rod while removing
pump module.
(6) Rotate clip (2) (Fig. 13) to release float rod (3)
from fuel level sensor (1).(7) Twist rod (3) slightly (Fig. 14) to remove from
fuel level sensor. Do not allow float assembly to fall
into fuel tank.
(8) While holding float rod, remove fuel pump
module from fuel tank.
(9) Remove float assembly from fuel tank.
(10) Remove and discard rubber gasket (seal) from
pump module.
Fig. 11 FUEL PUMP MODULE R/I
1 - LOCKNUT (LOCKRING)
2 - SPECIAL TOOL #6856
3 - TOP OF PUMP MODULE
Fig. 12 FLOAT ROD CLIP
1 - FUEL LEVEL SENSOR
2 - CLIP
3 - FLOAT ROD
Fig. 13 FLOAT ROD CLIP REMOVAL
1 - FUEL LEVEL SENSOR
2 - CLIP
3 - FLOAT ROD
Fig. 14 FLOAT ROD CLIP REMOVED
1 - FUEL LEVEL SENSOR
2 - CLIP
3 - FLOAT ROD
VAFUEL DELIVERY 14 - 19