sensor MERCEDES-BENZ SPRINTER 2006 Service Manual

Switching Off Main Injection
Main injection is switched off when:
²Engine speed is too high >4700 - 4800 rpm
²Main injection quantity too low
²Low fuel pressure in fuel rail
²Engine off
²External quantity control
²Deceleration mode
Calculating Main Injection
The quantity of main injection is calculated by:
²Engine speed
²Atmospheric pressure
²Coolant temperature
²Boost air temperature
²Fuel rail pressure
²Boost pressure
Period of Actuation
For calculating the period of actuation of the main
injection it is necessary to know whether a pre-injec-
tion has occurred or not.
The coolant temperature, charge air temperature
and the atmospheric pressure are used for correcting
the main injection quantity. If main injection quan-
tity is less than a minimum quantity which is depen-
dent on fuel rail pressure, no preinjection takes
place. In this case, only main injection is performed.
If the quantity is then still below the minimum
quantity, neither main injection or pre-injection takes
place (deceleration mode).
Deceleration Mode
The purpose of the deceleration mode is to inter-
rupt the operation of the injectors. The ECM deter-
mines the accelerator pedal position from a supplied
signal and it determines the engine speed by the
crank sensor. In the overrun and with the engine
speed above 1600, with the accelerator pedal no
pressed, the injectors are no longer actuated and the
fuel rail pressure is lowered by the pressure regula-
tor valve.
Full Load Injected Quantity
The purpose of the full load injected quantity is to
minimize the formation of smoke. The ECM limits
the fuel rail pressure when the engine is operating at
full load by way of the quantity control valve, and
quantity of fuel injected by the injectors. this mini-
mizes the formation of smoke when accelerating and
driving at constant speeds. If a fault occurs at the
boost pressure control, full load injected quantity is
reduced.
Limiting Maximum Engine Speed
The ECM determines the engine speed based on
the signal supplied by the crankshaft sensor and lim-its this by interrupting the operation of the fuel
injectors.
Fuel Quantity Control
The fuel quantity is controlled separately for each
cylinder by the ECM inline with the firing order.The
ECM detects the operating state which exists at the
engine by means of the sensors. In order adapt the
quantity injected, either the fuel rail pressure can be
adjusted by the fuel solenoid and quantity control
valve or the actuation time of the solenoid valves in
the injectors
Boiling Protection
In order to protect against thermal overload and
along with criteria programmed in the ECM, the
injection quantity is reduced as a function of the cool-
ant temperature and vehicle speed. If the coolant
temperature sensor fails the oil temperature signal
from the oil sensor is used as a suitable value.
Fuel Tank Protection
The fuel rail pressure is lowered in order to protect
the fuel tank from overheating. The fuel temperature
sensor measures the temperature of the fuel being
supplied from the tank, in the high pressure flange.
If the fuel is too warm the fuel rail pressure is fur-
ther reduced by the quantity control valve.
STANDARD PROCEDURE
STANDARD PROCEDURE - DRAINING FUEL
TANK - DIESEL
(1) Position a drain hose into the fuel fill opening.
(2) Drain fuel tank using an approved diesel fuel
draining station.
FUEL CONTAMINATION
If a diesel engine's fuel supply has been contami-
nated with gasoline, the following procedure must be
followed:
(1) Remove all fuel from the fuel tank. (Refer to 14
- FUEL SYSTEM/FUEL DELIVERY - STANDARD
PROCEDURE-DRAINING FUEL TANK) Use an
appropriate fuel container. Dispose of the contami-
nated fuel using the proper procedures.
CAUTION: Dispose of petroleum based products in
a manner consistent with all applicable Local, State,
Federal, and Provincial regulations.
(2) Remove and clean fuel tank. (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/FUEL TANK -
REMOVAL)
(3) Install the fuel tank. (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/FUEL TANK - INSTALLA-
TION)
14 - 8 FUEL DELIVERYVA

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

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

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

INSTALLATION
CAUTION: Whenever the fuel pump module is ser-
viced, the rubber gasket must be replaced.
(1) Thoroughly clean locknut (lockring) and lock-
nut threads at top of tank.
(2) Position new gasket (seal) to fuel tank opening.
(3) Position float rod assembly partially into fuel
tank.
(4) Position fuel pump module partially into fuel
tank.
(5) Twist rod (3) (Fig. 15) into clip (2) on fuel level
sensor (1).
(6) Rotate clip (2) (Fig. 16) to attach rod (3) to
clip.(7) After attaching float assembly to fuel level sen-
sor, carefully position fuel pump module into opening
in fuel tank.
(8) Position locknut over top of fuel pump module.
Install locknut finger tight.
(9) The fuel line fittings should be pointed to the
right side of the vehicle. Rotate and position align-
ment arrow (Fig. 17) towards right side of vehicle (if
necessary) before tightening locknut.This step
must be performed to prevent the module's
float from contacting the side of fuel tank.
(10) Tighten locknut using Special Tool #6856.
Refer to Torque Specifications.
(11) Install fuel tank. Refer to Fuel Tank Removal/
Installation.
Fig. 15 FLOAT ROD CLIP INSTALLATION
1 - FUEL LEVEL SENSOR
2 - CLIP
3 - FLOAT ROD
Fig. 16 FLOAT ROD CLIP INSTALLATION
1 - FUEL LEVEL SENSOR
2 - CLIP
3 - FLOAT ROD
14 - 20 FUEL DELIVERYVA