2005 MERCEDES-BENZ SPRINTER engine

INSTALLATION
(1) (Refer to 14 - FUEL SYSTEM/FUEL INJEC-
TION - WARNING) Install the sealing ring on to the
sensor (Fig. 13).
(2) Screw the sensor in to the fuel rail. Counter-
hold the threaded connection and tighten the sensor
to 18 lbs. ft. (25 N´m.) (Fig. 13).
(3) Connect the wiring harness to the sensor.
(4) Install the mixing housing.
(5) Connect negative battery cable.
FUEL PRESSURE SOLENOID
DESCRIPTION
The fuel pressure solenoid is attached to the rear
of the fuel rail. The solenoid controls and maintains
the rail pressure constant along with a control cur-
rent transmitted by the engine control module (ECM)
(Fig. 14).
OPERATION
High pressure which is present in the fuel rail
flows to the ball seat of the solenoid (Fig. 15). The
specified pressure required by the system is built up
in the rail by the fuel pressure solenoid building up a
magnetic force which corresponds to this specific
pressure by means of a control current from the elec-
tronic control module (ECM) (Fig. 15). This magnetic
force equals a certain outlet cross section at the ball
seat of the solenoid. The rail pressure is altered as a
result of the quantity of fuel which flows off (Fig. 15).
The current fuel pressure is signaled by the fuel
pressure sensor to the engine control module (ECM).
The controlled fuel flows back along the return fuel
line, into the tank.
In a de-energized state, the fuel pressure solenoid
is closed as the spring force presses the ball into the
ball seat (Fig. 15). When driving, the fuel pressure
solenoid is constantly open (Fig. 15). When engine is
started, the fuel pressure solenoid is held closed by
magnetic force (Fig. 15). When driving, the pressure
of the fluid counteracts the magnetic force of the coil
and the slight spring force (Fig. 15).
Fig. 14 FUEL PRESSURE SOLENOID - TYPICAL
1 - INJECTION LINES
2 - FUEL RAIL
3 - FUEL RETURN LINE
4 - FUEL PRESSURE SOLENOID
5 - OIL LINE
6 - SEALS
7 - FUEL RETURN LINE AT COOLER
8 - HIGH PRESSURE FUEL LINE TO FUEL RAIL
9 - FUEL LINE BRACKET
10 - FUEL PRESSURE SENSOR
Fig. 15 FUEL PRESSURE SOLENOID OPERATION
1 - BALL SEAT
2 - SPRING FORCE
3 - MAGNETIC FORCE
4 - COIL
5 - FUEL PRESSURE SOLENOID
6 - HIGH PRESSURE FEED
VAFUEL INJECTION 14 - 27
FUEL PRESSURE SENSOR (Continued)

WARNING: USE EXTREME CAUTION WHEN ENGINE
IS OPERATING. DO NOT PUT YOUR HANDS NEAR
PULLEYS, BELTS, OR FAN. DO NOT WEAR LOOSE
CLOTHES.
(4) Start engine and inspect for leaks (Refer to 14 -
FUEL SYSTEM - DIAGNOSIS AND TESTING).
FUEL TEMPERATURE SENSOR
DESCRIPTION
The fuel temperature sensor is located in the fuel
return line directly down stream of the fuel rail pres-
sure control valve. The sensor measures the temper-
ature of the fuel in the return pipe between the rail
and the pre-heating valve. The sensor ranges from -
40ÉF (- 40C) to 284ÉF (140ÉC). If the engine is cold,
the actual value sent will read ambient temperature.
The value rises after the engine has been started.
OPERATION
An negative temperature coefficient (NTC) resistor
integrated in the fuel temperature sensor alters it's
electrical resistance in line with the fuel temperature
(the resistance drops as the temperature rises). If
fuel temperature has reached 248ÉF and engine
speed is above 2000 rpm, a pumping element of the
high pressure fuel injection pump is switched off and
engine output is reduced.
REMOVAL
(1) Disconnect the negative battery cable.
(2) Disconnect the sensor wiring harness connector
(Refer to 14 - FUEL SYSTEM/FUEL INJECTION -
WARNING).
(3) Remove the fuel temperature sensor from the
fuel rail (Fig. 17).
INSTALLATION
(1) Clean sealing surfaces.
(2) Install new seal on sensor (Fig. 17).
(3) Screw the sensor into the fuel rail and tighten
to 18 lbs.ft. (25 N´m)(Refer to 14 - FUEL SYSTEM/
FUEL INJECTION - WARNING) . (Fig. 17)
(4) Connect negative battery cable.
INLET AIR TEMPERATURE
SENSOR
DESCRIPTION
The inlet air temperature sensor is located
between the charge air pipe and the charge air dis-
tribution of the cylinders. The inlet air temperature
sensor measures the temperature of the air as it is
supplied to the cylinders and transmits the value to
the ECM. This is required in order to determine the
density of the air being supplied for the combustion
process. The value range is from minus 40ÉF up to
302ÉF (minus 40ÉC to 150ÉC).
OPERATION
The Negative Temperature Coefficient (NTC)
resister located within the inlet air temperature sen-
sor alters it's resistance in line with the charge air
temperature. If the engine is cold, the value equals
ambient temperature. For a temperature of 68ÉF
(20ÉC) the resistance is approximately 6000 ohms.
For a temperature of 104ÉF (40ÉC) the resistance is
approximately 2600 ohms (Fig. 18).
Fig. 17 FUEL TEMPERATURE SENSOR
1 - FUEL RAIL
2 - FUEL TEMPERATURE SENSOR
3 - HARNESS CONNECTOR
4 - SEAL
VAFUEL INJECTION 14 - 29
FUEL PRESSURE SOLENOID (Continued)

STEERING
TABLE OF CONTENTS
page page
STEERING
DESCRIPTION..........................1
OPERATION............................1
DIAGNOSIS AND TESTING - POWER
STEERING SYSTEM....................2COLUMN...............................5
GEAR..................................8
LINKAGE..............................10
PUMP.................................12
STEERING
DESCRIPTION
CAUTION: Mopar ATF+4 Automatic Transmission
fluid or equivalent is to be used in the power steer-
ing system. No other power steering or automatic
transmission fluid is to be used in the system.
Damage may result to the power steering pump and
system if any other fluid is used, and do not over-
fill.
Power steering systems consist of:
²Steering column
²Rack and pinion steering gear
²Belt driven hydraulic steering pump
²Pump pressure and return hoses
²Oil Cooler
OPERATION
The steering column shaft is attached to the gear
pinion. The rotation of the pinion moves the gear
rack from side-to-side. This lateral action of the rack
pushes and pulls the tie rods to change the direction
of the front wheels (Fig. 1).
Power assist is provided by an engine mounted
hydraulic pump which supplies hydraulic fluid pres-
sure to the steering gear.
Fig. 1 STEERING COMPONENTS
1 - POWER STEERING PUMP ASSEMBLY
2 - RESERVOIR
3 - HOSES
4 - TIE ROD ENDS
5 - MOUNTING BOLTS
6 - RACK & PINION
VASTEERING 19 - 1

GEAR
TABLE OF CONTENTS
page page
GEAR
DESCRIPTION..........................8
REMOVAL.............................8INSTALLATION..........................8
SPECIFICATIONS - TORQUE CHART.........9
GEAR
DESCRIPTION
A rack and pinion steering gears (Fig. 1) is made
up of two main components, the pinon shaft and the
rack. The gear cannot be adjusted or internally ser-
viced. If a malfunction or a fluid leak occurs, the gear
must be replaced as an assembly.
REMOVAL
(1) Siphon the power steering fluid out of the res-
ervoir.
(2) Raise and support the vehicle.
(3) Remove the front wheels.
(4) Remove the stabilizer bar from the upper part
of the stabilizer link (Refer to 2 - SUSPENSION/
FRONT/STABILIZER LINK - REMOVAL).
(5) Remove the outer tie rod end nuts and sepa-
rate the tie rods from the steering knuckles (Fig. 2)
using special tool C-3894±A.
(6) Remove the left outer tie rod end from the
steering gear.(7) Remove both spring clamp plates (Refer to 2 -
SUSPENSION/FRONT/SPRING CLAMP PLATES -
REMOVAL).
(8) Remove both the high pressure and return
hoses from the steering gear (Refer to 19 - STEER-
ING/PUMP/HOSES - REMOVAL) (Fig. 2).
(9) Remove the steering shaft clamping bolt from
the steering gear (Fig. 2).
(10) Separate the universal joint from the steering
gear (Fig. 2).
(11) Remove the steering gear bolts from the front
axle.
(12) Remove the steering gear by sliding it toward
the passengers side of the vehicle and then tilt down-
ward on the drivers side and remove from vehicle.
INSTALLATION
(1) Install the gear to the vehicle.
Fig. 1 STEERING GEAR
1 - OUTER TIE ROD ENDS
2 - MOUNTING BUSHINGS
3 - BELLOWS
Fig. 2 STEERING GEAR REMOVAL / INSTALL
1 - U-JOINT
2 - HIGH PRESSURE POWER STEERING HOSE
3 - RETURN HOSE
4 - OUTER TIE ROD END RETAINING NUT
5 - STEERING GEAR
6 - STEERING GEAR RETAINING BOLT
7 - STEERING GEAR NUT
8 - WASHER
9 - ENGINE MOUNT BOLT
10 - U-JOINT CLAMPING BOLT
19 - 8 GEARVA

PUMP
TABLE OF CONTENTS
page page
PUMP
DESCRIPTION.........................12
OPERATION...........................12
DIAGNOSIS AND TESTING - PUMP LEAKAGE . 12
STANDARD PROCEDURE
STANDARD PROCEDURE - POWER
STEERING PUMP - INITIAL OPERATION....12
STANDARD PROCEDURE - FLUSHING
POWER STEERING SYSTEM............13
REMOVAL.............................13
INSTALLATION.........................13
SPECIFICATIONS - TORQUE CHART........14
FLUID
STANDARD PROCEDURE
POWER STEERING PUMP FILL AND BLEED
PROCEDURE........................14FLUID COOLER TUBE
REMOVAL.............................14
INSTALLATION.........................14
HOSES
REMOVAL
REMOVAL - PRESSURE HOSE...........15
REMOVAL - RETURN LINE FROM PUMP TO
COOLER TUBE.......................15
REMOVAL - RETURN HOSE FROM GEAR
TO COOLER TUBE....................15
INSTALLATION
INSTALLATION - PRESSURE HOSE.......15
INSTALLATION - RETURN LINE FROM
PUMP TO COOLER TUBE...............15
INSTALLATION - RETURN HOSE FROM
GEAR TO COOLER TUBE...............15
PUMP
DESCRIPTION
CAUTION: Mopar ATF+4 Automatic Transmission
fluid or equivalent is to be used in the power steer-
ing system. No other power steering or automatic
transmission fluid is to be used in the system.
Damage may result to the power steering pump and
system if any other fluid is used, and do not over-
fill.
The pump is connected to the steering gear via the
pressure hose and the return hose. The pump shaft
has a pressed-on pulley that is belt driven by the
crankshaft pulley.
All vehicles are equipped with a power steering
fluid cooler.
NOTE: Power steering pumps are not interchange-
able with pumps installed on other vehicles.
OPERATION
Hydraulic pressure is provided for the power steer-
ing gear by the belt driven power steering pump. The
power steering pumps are constant flow rate and dis-
placement, vane-type pumps.
DIAGNOSIS AND TESTING - PUMP LEAKAGE
The pump is serviced as an assembly and should
not be disassembled. The plastic pump reservoir and
the reservoir o-rings can be replaced.
Check for leaks in the following areas:
²Pump shaft seal behind the pulley
²Pump to reservoir O-ring
²Reservoir cap
²Pressure and return lines
²Flow control valve fitting
STANDARD PROCEDURE
STANDARD PROCEDURE - POWER STEERING
PUMP - INITIAL OPERATION
WARNING: THE FLUID LEVEL SHOULD BE
CHECKED WITH ENGINE OFF TO PREVENT INJURY
FROM MOVING COMPONENTS.
CAUTION: Mopar ATF+4 Automatic Transmission
fluid or equivalent is to be used in the power steer-
ing system. No other power steering or automatic
transmission fluid is to be used in the system.
Damage may result to the power steering pump and
system if any other fluid is used, and do not over-
fill.
19 - 12 PUMPVA

Wipe filler cap clean, then check the fluid level.
The dipstick should indicateCOLDwhen the fluid is
at normal temperature.
(1) Turn steering wheel all the way to the left
(2) Fill the pump fluid reservoir to the proper level
and let the fluid settle for at least two (2) minutes.
(3) Raise the front wheels off the ground.
(4)
Slowly turn the steering wheel lock-to-lock 20
times with the engine off while checking the fluid level.
NOTE: For vehicles with long return lines or oil
coolers turn wheel 40 times.
(5) Start the engine. With the engine idling main-
tain the fluid level.
(6) Lower the front wheels and let the engine idle
for two minutes.
(7) Turn the steering wheel in both direction and
verify power assist and quiet operation of the pump.
If the fluid is extremely foamy or milky looking,
allow the vehicle to stand a few minutes and repeat
the procedure.
CAUTION: Do not run a vehicle with foamy fluid for
an extended period. This may cause pump damage.
STANDARD PROCEDURE - FLUSHING POWER
STEERING SYSTEM
Flushing is required when the power steering/hy-
draulic booster system fluid has become contami-
nated. Contaminated fluid in the steering/booster
system can cause seal deterioration and affect steer-
ing gear/booster spool valve operation.
(1) Raise the front end of the vehicle off the
ground until the wheels are free to turn.
(2) Remove the return line from the pump.
NOTE: If vehicle is equipped with a hydraulic
booster remove both return lines from the pump.
(3) Plug the return line port/ports at the pump.
(4) Position the return line/lines into a large con-
tainer to catch the fluid.
(5) While an assistant is filling the pump reservoir
start the engine.
(6) With the engine running at idle turn the wheel
back and forth.
NOTE: Do not contact or hold the wheel against the
steering stops.
(7) Run a quart of fluid through the system then
stop the engine and install the return line/lines.
(8) Fill the system with fluid and perform Steering
Pump Initial Operation, (Refer to 19 - STEERING/
PUMP - STANDARD PROCEDURE).(9) Start the engine and run it for fifteen minutes
then stop the engine.
(10) Remove the return line/lines from the pump
and plug the pump port/ports.
(11) Pour fresh fluid into the reservoir and check
the draining fluid for contamination. If the fluid is
still contaminated, then flush the system again.
(12) Install the return line/lines and perform
Steering Pump Initial Operation, (Refer to 19 -
STEERING/PUMP - STANDARD PROCEDURE).
REMOVAL
(1) Remove the belt from the power steering pump.
(2) Siphon as much power steering fluid as possi-
ble out of the reservoir.
(3) Remove the high pressure power steering hose
at the pump (Fig. 1).
(4)
Remove the return hose from the pump (Fig. 1).
(5) Remove the bolts securing the power steering
pump to the engine (Fig. 1).
INSTALLATION
(1) Install the power steering pump to the engine
and tighten the bolts (Fig. 1). Tighten to 21 N´m (15
ft. lbs.).
(2) Replace all o-rings and hose clamps (Fig. 1).
(3) Install the return hose to the pump and tighten
the clamp (Fig. 1).
(4) Install the high pressure hose to the pump
(Fig. 1). Tighten to 38 N´m (28 ft. lbs.).
(5)
Fill the power steering fluid (Refer to 19 - STEER-
ING/PUMP/FLUID - STANDARD PROCEDURE).
Fig. 1 POWER STEERING PUMP
1 - PUMP MOUNTING BOLT
2 - CLAMP
3 - RETURN HOSE
4 - HIGH PRESSURE HOSE
5 - O-RING
6 - PUMP RESERVOIR
7 - PUMP
8 - PULLEY
9 - PULLEY BOLT
VAPUMP 19 - 13
PUMP (Continued)

SPECIFICATIONS - TORQUE CHART
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Power Steering Pump To
Timing Case Cover/
Support21 15 185
High Pressure Flexible
Hose To Power Steering
Pump38 28 336
Power Steering Pulley To
Pump30 22 265
FLUID
STANDARD PROCEDURE
POWER STEERING PUMP FILL AND BLEED
PROCEDURE
(1) Remove the cap from the fluid reservoir.
Check cap seal for damage and replace if
needed.
(2) Fill the power steering pump with Mopar
ATF+4 Automatic Transmission fluid or equivalent.
Do not fill fluid beyond the MAX mark.
(3) Raise the vehicles front wheels off the ground.
(4) With the engine off turn the steering wheel
from right to left.Perform this step until all the
bubble formations can no longer be seen in the
power steering reservoir.
(5) Start the engine and turn the steering wheel
with the engine at idle speed then shut the engine off
and check for correct oil level and no bubble in the
system.
(6) Reinstall power steering cap tightly.
(7) Test the system for leaks and proper operation.
FLUID COOLER TUBE
REMOVAL
(1) Siphon as much power steering fluid as possi-
ble out of the reservoir.
(2) Remove the grille (Refer to 23 - BODY/EXTE-
RIOR/GRILLE - REMOVAL).
(3) Remove the left headlight assembly.
(4) Disconnect the return lines from the cooler
tube.
(5) Remove the radiator clips (2).
(6) Remove the heat shield bolt for the turbo at
the core support.
(7) Remove the right headlight assembly.(8) Remove the core support bolts (4) and discon-
nect the hood latch cable.
(9) Remove the fan bracket bolts (4) to the radiator
(Fig. 2).
(10) Remove the two upper screws for the con-
denser (Fig. 2).
(11) Remove the condenser air dam shield.
(12) Remove the mounting screws for the cooler
tube (Fig. 2).
(13) Remove the cooler tube from the vehicle.
INSTALLATION
(1) Install the cooler tube to the vehicle.
(2) Install the cooler tube mounting screws (Fig.
2).
(3) Install the condenser air dam shield.
(4) Install the condenser upper mounting screws
(Fig. 2).
Fig. 2 FLUID COOLER TUBE
1 - MOUNTING SCREWS (4)
2 - FLUID COOLER
3 - ELECTRIC COOLING FAN
4 - A/C CONDENSOR
19 - 14 PUMPVA
PUMP (Continued)

OUTPUT SHAFT SEAL
REMOVAL............................125
INSTALLATION........................125
PARK LOCK CABLE
REMOVAL............................125
INSTALLATION........................126
PISTONS
DESCRIPTION........................128
OPERATION..........................128
PLANETARY GEARTRAIN
DESCRIPTION........................130
OPERATION..........................130
DISASSEMBLY........................131
ASSEMBLY...........................131
SHIFT MECHANISM
DESCRIPTION........................133
OPERATION..........................133
REMOVAL............................134
INSTALLATION........................135
SOLENOID
DESCRIPTION........................136OPERATION..........................138
TEMPERATURE SENSOR/PARK-NEUTRAL
CONTACT
DESCRIPTION
DESCRIPTION - PARK/NEUTRAL CONTACT . 139
DESCRIPTION - TRANSMISSION
TEMPERATURE SENSOR..............140
OPERATION
OPERATION - PARK/NEUTRAL CONTACT . . 140
OPERATION - TRANSMISSION
TEMPERATURE SENSOR..............141
TORQUE CONVERTER
DESCRIPTION........................141
OPERATION..........................143
REMOVAL............................146
INSTALLATION........................146
TORQUE CONVERTER HUB SEAL
REMOVAL............................147
INSTALLATION........................147
AUTOMATIC TRANSMISSION -
NAG1
DESCRIPTION
The NAG1 automatic transmission (Fig. 1) is an
electronically controlled 5-speed transmission with a
lock-up clutch in the torque converter. The ratios for
the gear stages are obtained by 3 planetary gear sets.
Fifth gear is designed as an overdrive with a high-
speed ratio.
The gears are actuated electronically/hydraulically.
The gears are shifted by means of an appropriate
combination of three multi-disc holding clutches,
three multi-disc driving clutches, and two freewheel-
ing clutches.
Electronic transmission control enables precise
adaptation of pressures to the respective operating
conditions and to the engine output during the shift
phase which results in a significant improvement in
shift quality.
Furthermore, it offers the advantage of a flexible
adaptation to various vehicle and engines.
Basically, the automatic transmission with elec-
tronic control offers the following advantages:
²Reduces fuel consumption.
²Improved shift comfort.
²More favourable step-up through the five gears.
²Increased service life and reliability.
²Lower maintenance costs.
TRANSMISSION IDENTIFICATION
The transmission name, NAG1, means New Auto-
matic Gearbox, generation 1.
The transmission can be generically identified
visually by the presence of a round 13-way connector
located near the front corner of the transmission oil
pan, on the right side. Specific transmission informa-
tion can be found stamped into a pad on the left side
of the transmission, above the oil pan rail.
TRANSMISSION GEAR RATIOS
The gear ratios for the NAG1 automatic transmis-
sion are as follows:
1st Gear.............................3.59:1
2nd Gear............................2.19:1
3rd Gear............................1.41:1
4th Gear............................1.00:1
5th Gear............................0.83:1
Reverse.............................3.16:1
TRANSMISSION HOUSING
The converter housing and transmission are made
from a light alloy. These are bolted together and cen-
tered via the outer multi-disc carrier of multi-disc
holding clutch, B1. A coated intermediate plate pro-
vides the sealing. The oil pump and the outer multi-
disc carrier of the multi-disc holding clutch, B1, are
bolted to the converter housing. The stator shaft is
pressed into it and prevented from rotating by
splines. The electrohydraulic unit is bolted to the
transmission housing from underneath. A sheet
metal steel oil pan forms the closure.
21 - 2 AUTOMATIC TRANSMISSION - NAG1VA