2003 DODGE RAM throttle sensor

(4) Check condition of sensor o-ring.
5.7L V-8
The intake manifold air temperature (IAT) sensor
is installed into the front of the intake manifold air
box plenum (Fig. 27).
(1) Disconnect electrical connector from IAT sensor
(Fig. 27).
(2) Clean dirt from intake manifold at sensor base.
(3) Gently lift on small plastic release tab (Fig. 25)
or (Fig. 28) and rotate sensor about 1/4 turn counter-
clockwise for removal.
(4) Check condition of sensor o-ring.
5.9L
The intake manifold air temperature sensor is
located in the front/side of the intake manifold (Fig.
29).
(1) Clean dirt from intake manifold at sensor base.
(2) Disconnect electrical connector at sensor (Fig.
29).
(3) Remove sensor from intake manifold.
8.0L V-10
The intake manifold air temperature sensor is
located in the side of the intake manifold near the
front of throttle body (Fig. 30).
(1) Disconnect electrical connector at sensor.
(2) Remove sensor from intake manifold.
Fig. 25 IAT SENSOR TAB / O-RING - 3.7L V-6/4.7L
V-8/5.7L V-8
1 - IAT SENSOR
2 - SENSOR O-RING
3 - RELEASE TAB
Fig. 26 IAT SENSOR - 4.7L V-8
1 - LEFT SIDE OF THROTTLE BODY
2 - ELEC. CONNECT.
3 - IAT SENSOR
4 - RELEASE TAB
Fig. 27 5.7L IAT SENSOR LOCATION
1 - FRONT OF INTAKE MANIFOLD PLENUM
2 - IAT ELECTRICAL CONNECTOR
DRFUEL INJECTION - GAS 14 - 37
INTAKE AIR TEMPERATURE SENSOR (Continued)

INSTALLATION
3.7L V-6
The intake manifold air temperature (IAT) sensor
is installed into the left side of intake manifold ple-
num (Fig. 24).
(1) Check condition of sensor o-ring.(2) Clean sensor mounting hole in intake manifold.
(3) Position sensor into intake manifold and rotate
clockwise until past release tab (Fig. 24).
(4) Install electrical connector.
4.7L V-8
The intake manifold air temperature (IAT) sensor
is installed into the left side of intake manifold ple-
num (Fig. 26).
(1) Check condition of sensor o-ring.
(2) Clean sensor mounting hole in intake manifold.
(3) Position sensor into intake manifold and rotate
clockwise until past release tab.
(4) Install electrical connector.
5.7L V-8
The intake manifold air temperature (IAT) sensor
is installed into the front of the intake manifold air
box plenum (Fig. 27).
(1) Check condition of sensor o-ring.
(2) Clean sensor mounting hole in intake manifold.
(3) Position sensor into intake manifold and rotate
clockwise until past release tab.
(4) Install electrical connector.
5.9L V-8
The intake manifold air temperature sensor is
located in the front/side of the intake manifold (Fig.
29).
(1) Install sensor to intake manifold. Tighten to
12±15 N´m (110±130 in. lbs.) torque.
(2) Install electrical connector.
8.0L V-10
The intake manifold air temperature sensor is
located in the side of the intake manifold near the
front of throttle body (Fig. 30).
Fig. 28 5.7L IAT SENSOR R/I
1 - FRONT OF INTAKE MANIFOLD PLENUM
2 - IAT SENSOR
3 - RELEASE TAB
Fig. 29 IAT SENSOR LOCATION - 5.9L
1 - INTAKE MANIFOLD AIR TEMPERATURE SENSOR
2 - ELECTRICAL CONNECTOR
Fig. 30 AIR TEMPERATURE SENSOR - 8.0L V-10
1 - INTAKE MANIFOLD AIR TEMP. SENSOR
2 - INTAKE MANIFOLD
14 - 38 FUEL INJECTION - GASDR
INTAKE AIR TEMPERATURE SENSOR (Continued)

(1) Install sensor to intake manifold. Tighten to
12±15 N´m (110±130 in. lbs.) torque.
(2) Install electrical connector.
MAP SENSOR
DESCRIPTION
3.7L V-6
The Manifold Absolute Pressure (MAP) sensor is
mounted into the front of the intake manifold with 2
screws.
4.7L V-8
The Manifold Absolute Pressure (MAP) sensor is
mounted into the front of the intake manifold with 2
screws.
5.7L V-8
The Manifold Absolute Pressure (MAP) sensor is
mounted to the front of the intake manifold air ple-
num box.
5.9L V-8
The Manifold Absolute Pressure (MAP) sensor is
mounted to the front of the throttle body with 2
screws.
8.0L V-10
The Manifold Absolute Pressure (MAP) sensor is
mounted into the right side of the intake manifold.
OPERATION
The MAP sensor is used as an input to the Power-
train Control Module (PCM). It contains a silicon
based sensing unit to provide data on the manifold
vacuum that draws the air/fuel mixture into the com-
bustion chamber. The PCM requires this information
to determine injector pulse width and spark advance.
When manifold absolute pressure (MAP) equals
Barometric pressure, the pulse width will be at max-
imum.
A 5 volt reference is supplied from the PCM and
returns a voltage signal to the PCM that reflects
manifold pressure. The zero pressure reading is 0.5V
and full scale is 4.5V. For a pressure swing of 0±15
psi, the voltage changes 4.0V. To operate the sensor,
it is supplied a regulated 4.8 to 5.1 volts. Ground is
provided through the low-noise, sensor return circuit
at the PCM.
The MAP sensor input is the number one contrib-
utor to fuel injector pulse width. The most important
function of the MAP sensor is to determine baromet-
ric pressure. The PCM needs to know if the vehicle is
at sea level or at a higher altitude, because the airdensity changes with altitude. It will also help to cor-
rect for varying barometric pressure. Barometric
pressure and altitude have a direct inverse correla-
tion; as altitude goes up, barometric goes down. At
key-on, the PCM powers up and looks at MAP volt-
age, and based upon the voltage it sees, it knows the
current barometric pressure (relative to altitude).
Once the engine starts, the PCM looks at the voltage
again, continuously every 12 milliseconds, and com-
pares the current voltage to what it was at key-on.
The difference between current voltage and what it
was at key-on, is manifold vacuum.
During key-on (engine not running) the sensor
reads (updates) barometric pressure. A normal range
can be obtained by monitoring a known good sensor.
As the altitude increases, the air becomes thinner
(less oxygen). If a vehicle is started and driven to a
very different altitude than where it was at key-on,
the barometric pressure needs to be updated. Any
time the PCM sees Wide Open Throttle (WOT), based
upon Throttle Position Sensor (TPS) angle and RPM,
it will update barometric pressure in the MAP mem-
ory cell. With periodic updates, the PCM can make
its calculations more effectively.
The PCM uses the MAP sensor input to aid in cal-
culating the following:
²Manifold pressure
²Barometric pressure
²Engine load
²Injector pulse-width
²Spark-advance programs
²Shift-point strategies (certain automatic trans-
missions only)
²Idle speed
²Decel fuel shutoff
The MAP sensor signal is provided from a single
piezoresistive element located in the center of a dia-
phragm. The element and diaphragm are both made
of silicone. As manifold pressure changes, the dia-
phragm moves causing the element to deflect, which
stresses the silicone. When silicone is exposed to
stress, its resistance changes. As manifold vacuum
increases, the MAP sensor input voltage decreases
proportionally. The sensor also contains electronics
that condition the signal and provide temperature
compensation.
The PCM recognizes a decrease in manifold pres-
sure by monitoring a decrease in voltage from the
reading stored in the barometric pressure memory
cell. The MAP sensor is a linear sensor; meaning as
pressure changes, voltage changes proportionately.
The range of voltage output from the sensor is usu-
ally between 4.6 volts at sea level to as low as 0.3
volts at 26 in. of Hg. Barometric pressure is the pres-
sure exerted by the atmosphere upon an object. At
sea level on a standard day, no storm, barometric
DRFUEL INJECTION - GAS 14 - 39
INTAKE AIR TEMPERATURE SENSOR (Continued)

5.7L V-8
The Manifold Absolute Pressure (MAP) sensor is
mounted to the front of the intake manifold air ple-
num box (Fig. 34).
(1) Disconnect electrical connector at sensor by
sliding release lock out (Fig. 35). Press down on lock
tab for removal.
(2) Rotate sensor 1/4 turn counter-clockwise for
removal.
(3) Check condition of sensor o-ring.
5.9L V-8
The MAP sensor is located on the front of the
throttle body (Fig. 36). An L-shaped rubber fitting is
used to connect the MAP sensor to throttle body (Fig.
37).
(1) Clean area around MAP sensor.
(2) Remove two MAP sensor mounting bolts
(screws) (Fig. 36).
(3) While removing MAP sensor, slide the vacuum
rubber L-shaped fitting (Fig. 37) from the throttle
body.
(4) Remove rubber L-shaped fitting from MAP sen-
sor.
8.0L V-10
The MAP sensor is mounted into the right upper
side of intake manifold (Fig. 38). A rubber gasket is
used to seal sensor to intake manifold. The rubber
gasket is part of sensor and is not serviced sepa-
rately.(1) Remove electrical connector at sensor.
(2) Clean area around sensor before removal.
(3) Remove two sensor mounting bolts.
(4) Remove sensor from intake manifold.
Fig. 34 5.7L MAP SENSOR LOCATION
1 - MAP SENSOR
2 - FRONT OF INTAKE MANIFOLD
Fig. 35 5.7L MAP SENSOR R/I
1 - PRESS DOWN
2 - SLIDE RELEASE LOCK
3 - MAP SENSOR
Fig. 36 MAP SENSOR - 5.9L V-8
1 - MAP SENSOR
2 - MOUNTING SCREWS (2)
DRFUEL INJECTION - GAS 14 - 41
MAP SENSOR (Continued)

INSTALLATION
3.7L V-6
The Manifold Absolute Pressure (MAP) sensor is
mounted into the front of the intake manifold (Fig.
31). An o-ring is used to seal the sensor to the intake
manifold (Fig. 32).
(1) Clean MAP sensor mounting hole at intake
manifold.
(2) Check MAP sensor o-ring seal for cuts or tears.
(3) Position sensor into manifold.(4) Install MAP sensor mounting bolts (screws).
Refer to Torque Specifications.
(5) Connect electrical connector.
4.7L V-8
The MAP sensor is located on the front of the
intake manifold (Fig. 33). An o-ring seals the sensor
to the intake manifold (Fig. 32).
(1) Clean MAP sensor mounting hole at intake
manifold.
(2) Check MAP sensor o-ring seal for cuts or tears.
(3) Position sensor into manifold.
(4) Install MAP sensor mounting bolts (screws).
Refer to Torque Specifications.
(5) Connect electrical connector.
5.7L V-8
The Manifold Absolute Pressure (MAP) sensor is
mounted to the front of the intake manifold air ple-
num box (Fig. 34).
(1) Clean MAP sensor mounting hole at intake
manifold.
(2) Check MAP sensor o-ring seal for cuts or tears.
(3) Position sensor into manifold.
(4) Rotate sensor 1/4 turn clockwise for installa-
tion.
(5) Connect electrical connector.
5.9L V-8
The MAP sensor is located on the front of the
throttle body (Fig. 36). An L-shaped rubber fitting is
used to connect the MAP sensor to throttle body (Fig.
37).
(1) Install rubber L-shaped fitting to MAP sensor.
(2) Position sensor to throttle body while guiding
rubber fitting over throttle body vacuum nipple.
(3) Install MAP sensor mounting bolts (screws).
Refer to Torque Specifications.
(4) Install air resonator box.
8.0L V-10
The MAP sensor is mounted into the right upper
side of intake manifold (Fig. 38). A rubber gasket is
used to seal sensor to intake manifold. The rubber
gasket is part of sensor and is not serviced sepa-
rately.
(1) Check condition of sensor seal. Clean sensor
and lubricate rubber gasket with clean engine oil.
(2) Clean sensor opening in intake manifold.
(3) Install sensor into intake manifold.
(4) Install sensor mounting bolts. Refer to Torque
Specifications.
(5) Install electrical connector to sensor.
Fig. 37 MAP SENSOR L-SHAPED RUBBER FITTING
- 5.9L V-8
1 - MAP SENSOR
2 - RUBBER FITTING
3 - IDLE AIR PASSAGE
Fig. 38 MAP SENSOR LOCATION - 8.0L V-10
1 - MAP SENSOR
2 - MOUNTING BOLTS
3 - THROTTLE BODY
14 - 42 FUEL INJECTION - GASDR
MAP SENSOR (Continued)

INSTALLATION
Threads of new oxygen sensors are factory coated
with anti-seize compound to aid in removal.DO
NOT add any additional anti-seize compound to
threads of a new oxygen sensor.
(1) Install O2S sensor. Tighten to 30 N´m (22 ft.
lbs.) torque.
(2) Connect O2S sensor wire connector.
(3) Lower vehicle.
THROTTLE BODY
DESCRIPTION
The throttle body is located on the intake manifold.
Fuel does not enter the intake manifold through the
throttle body. Fuel is sprayed into the manifold by
the fuel injectors.
OPERATION
Filtered air from the air cleaner enters the intake
manifold through the throttle body. The throttle body
contains an air control passage controlled by an Idle
Air Control (IAC) motor. The air control passage is
used to supply air for idle conditions. A throttle valve
(plate) is used to supply air for above idle conditions.
5.7L V-8 Engine:
The throttle body on the 5.7L engine is an electri-
cally controlled unit. A mechanical cable is not used
to connect the throttle body to the accelerator pedal.
The Accelerator Pedal Position Sensor (APPS) along
with inputs from other sensors sets the throttle blade
to pre-determined positions.
Except 5.7L V-8 Engine:
Certain sensors are attached to the throttle body.
The accelerator pedal cable, speed control cable and
transmission control cable (when equipped) are con-
nected to the throttle body linkage arm.
A (factory adjusted) set screw is used to mechani-
cally limit the position of the throttle body throttle
plate.Never attempt to adjust the engine idle
speed using this screw.All idle speed functions are
controlled by the PCM.
REMOVAL
3.7L V-6
A (factory adjusted) set screw is used to mechani-
cally limit the position of the throttle body throttle
plate.Never attempt to adjust the engine idle
speed using this screw.All idle speed functions are
controlled by the Powertrain Control Module (PCM).
(1) Remove air cleaner tube at throttle body.
(2) Disconnect throttle body electrical connectors
at IAC motor and TPS.(3) Remove all control cables from throttle body
(lever) arm. Refer to the Accelerator Pedal and Throt-
tle Cable section for removal/installation procedures.
(4) Disconnect necessary vacuum lines at throttle
body.
(5) Remove 3 throttle body mounting bolts (Fig.
41).
(6) Remove throttle body from intake manifold.
(7) Check condition of old throttle body-to-intake
manifold o-ring (Fig. 42).
4.7L V-8
(1) Remove air duct and air resonator box at throt-
tle body.
(2) Disconnect throttle body electrical connectors
at IAC motor and TPS (Fig. 43).
(3) Remove vacuum line at throttle body.
(4) Remove all control cables from throttle body
(lever) arm. Refer to Accelerator Pedal and Throttle
Cable.
(5) Remove three throttle body mounting bolts
(Fig. 43).
(6) Remove throttle body from intake manifold.
5.7L V-8
CAUTION: Do not use spray (carb) cleaners on any
part of the throttle body. Do not apply silicone lubri-
cants to any part of the throttle body.
Fig. 41 THROTTLE BODY MOUNTING BOLTS - 3.7L
V-6
1 - THROTTLE BODY
2 - MOUNTING BOLTS (3)
DRFUEL INJECTION - GAS 14 - 45
OXYGEN SENSOR (Continued)

(1) Remove air duct and air resonator box at throt-
tle body.
(2) Disconnect electrical connector at throttle body
(Fig. 44).
(3) Remove 4 throttle body mounting bolts (Fig.
44).
(4) Remove throttle body from intake manifold.(5) Check condition of throttle body o-ring (Fig.
45).
(6) If the throttle body has been changed, the fol-
lowing procedure must be performed:
(a) Disconnect negative battery cable from bat-
tery. Leave cable disconnected for approximately 90
seconds.
(b) Reconnect cable to battery.
(c) Turn ignition switch ON, but do not crank
engine.
(d) Leave ignition switch ON for a minimum of
10 seconds. This will allow PCM to learn throttle
body electrical parameters.
5.9L V-8
A (factory adjusted) set screw is used to mechani-
cally limit the position of the throttle body throttle
plate.Never attempt to adjust the engine idle
speed using this screw.All idle speed functions are
controlled by the powertrain control module (PCM).
(1) Remove the air cleaner resonator tube.
(2) Disconnect throttle body electrical connectors
at MAP sensor, IAC motor and TPS (Fig. 46).
(3) Remove vacuum line at throttle body.
(4) Remove all control cables from throttle body
(lever) arm. Refer to the Accelerator Pedal and Throt-
tle Cable section of this group for additional informa-
tion.
Fig. 42 THROTTLE BODY O-RING - 3.7L V-6
1 - INTAKE MANIFOLD
2 - THROTTLE BODY O-RING
Fig. 43 THROTTLE BODY MOUNTING BOLTS - 4.7L
V-8
1 - MOUNTING BOLTS (3)
2 - THROTTLE BODY
3 - IAT SENSOR CONNECTOR
4 - IAC MOTOR CONNECTOR
5 - TPS CONNECTOR
Fig. 44 5.7L V-8 THROTTLE BODY
1 - THROTTLE BODY
2 - ELECTRICAL CONNECTOR
3 - SILICONE SEAL
4 - MOUNTING BOLTS (4)
14 - 46 FUEL INJECTION - GASDR
THROTTLE BODY (Continued)

(5) Remove four throttle body mounting bolts (Fig.
47).
(6) Remove throttle body from intake manifold.
(7) Discard old throttle body-to-intake manifold
gasket.8.0L V-10
A (factory adjusted) set screw is used to mechani-
cally limit the position of the throttle body throttle
plate.Never attempt to adjust the engine idle
speed using this screw.All idle speed functions are
controlled by the powertrain control module (PCM).
(1) Remove air plenum resonator.
(2) Disconnect throttle body electrical connectors
at the IAC motor and TPS.
(3) Remove all control cables from throttle body
(lever) arm. Refer to the Accelerator Pedal and Throt-
tle Cable section of this group for additional informa-
tion.
(4) Remove four throttle body mounting nuts (Fig.
48).
(5) Remove throttle body from intake manifold.
(6) Discard old throttle body-to-intake manifold
gasket.
INSTALLATION
3.7L V-6
(1) Check condition of throttle body-to-intake man-
ifold o-ring. Replace as necessary.
(2) Clean mating surfaces of throttle body and
intake manifold.
(3) Install throttle body-to-intake manifold o-ring.
(4) Install throttle body to intake manifold.
(5) Install 3 mounting bolts. Tighten bolts to 12
N´m (105 in. lbs.) torque.
Fig. 45 5.7L V-8 THROTTLE BODY O-RING
1 - INTAKE MANIFOLD
2 - THROTTLE BODY O-RING
Fig. 46 SENSOR ELECTRICAL CONNECTORS - 5.9L
V-8
1 - MAP SENSOR
2 - IDLE AIR CONTROL MOTOR
3 - THROTTLE POSITION SENSOR
Fig. 47 THROTTLE BODY MOUNTING BOLTS - 5.9L
V-8
1 - THROTTLE BODY MOUNTING BOLTS (4)
2 - THROTTLE BODY
DRFUEL INJECTION - GAS 14 - 47
THROTTLE BODY (Continued)