Dodge Ram Truck 1500-2500-3500. Manual — part 1489

c. Install high-pressure connector and retaining nut. Do a preliminary tightening to 15 N·m (11 ft. lbs.) torque.

d. Alternately tighten injector holdown bolts to 10 N·m (89 in. lbs.) torque.

e. Do a final tightening of the high-pressure connector and retaining nut. Tighten to 50 N·m (37 ft. lbs.) torque.

8. Connect injector solenoid wires and nuts to top of injectors. Tighten connector nuts to 1.25 N·m (11 in. lbs.)

torque. Be very careful not to overtighten these nuts as damage to fuel injector will occur.

9. Install exhaust rocker arm assembly. Refer to the Diesel Engine section.

10. Set exhaust valve lash. Refer to the Diesel Engine section.

11. Install high pressure fuel line. Refer to Torque Specifications. Be sure to use a secondary back-up wrench on

the connector nut (fitting) while torquing fuel line fitting. Refer to Fuel Line Installation for additional infor-
mation.

12. Install valve cover. Refer to the Diesel Engine section.

13. Install breather assembly.

14. Connect negative battery cables to both batteries.

RAIL - FUEL INJECTOR

DESCRIPTION

The fuel injector rail is bolted to the top of the intake manifold.

OPERATION

The fuel rail is used as a distribution device to supply high-pressure fuel to the high-pressure fuel lines.

REMOVAL

CAUTION: Cleanliness cannot be overemphasized when handling or replacing diesel fuel system compo-
nents. This especially includes the fuel injectors, high-pressure fuel lines and fuel injection pump. Very tight
tolerances are used with these parts. Dirt contamination could cause rapid part wear and possible plugging
of fuel injector nozzle tip holes. This in turn could lead to possible engine misfire. Always wash/clean any
fuel system component thoroughly before disassembly and then air dry. Cap or cover any open part after
disassembly. Before assembly, examine each part for dirt, grease or other contaminants and clean if nec-
essary. When installing new parts, lubricate them with clean engine oil or clean diesel fuel only.

1. Disconnect both negative battery cables at both batteries. Isolate ends of both cables.

2. Disconnect electrical connector at fuel pressure sensor.

3. Remove banjo bolt at fuel limiting valve.

4. Disconnect necessary wiring harness retention clips from intake manifold.

5. Lift 2 rubber covers to gain access to positive (+), intake heater cable nuts. Remove 2 nuts and remove 2 cables

from studs.

6. Carefully remove 4 high-pressure fuel lines from top of injector rail engine. Note position of each line while

removing. Do not bend lines while removing.

CAUTION: WHEN LOOSENING OR TIGHTENING HIGH-PRESSURE LINES ATTACHED TO A SEPARATE FIT-
TING, USE A BACK-UP WRENCH ON FITTING. DO NOT ALLOW FITTING TO ROTATE. DAMAGE TO BOTH
FUEL LINE AND FITTING WILL RESULT.

7. Carefully remove 2 high-pressure fuel lines at each end of injector rail. Note position of each line while removing.

Do not bend lines while removing.

8. Remove fuel line connecting injector pump to fuel rail.

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9. Remove three injector rail mounting bolts (3).

10. Remove rail from top of intake manifold.

INSTALLATION

1. Clean any dirt/debris from top of intake manifold and bottom of fuel rail.

2. Position fuel rail to top of manifold and install 3 mounting bolts finger tight.

3. Install all high-pressure lines to rail. Refer to Fuel Lines for procedures. Refer to Torque Specifications.

4. Tighten 3 mounting bolts at fuel rail. Refer to Torque Specifications.

5. Reposition wiring harness to intake manifold and install new tie wraps.

6. Install and tighten fuel limiting valve banjo bolt. Refer to Torque Specifications.

7. Connect electrical connector to fuel pressure sensor.

8. Position 2 positive (+) cables to intake heater studs. Install 2 nuts.

9. Connect battery cables to both batteries.

10. Start engine and check for leaks.

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SENSOR-TEMPERATURE/PRESSURE-INTAKE

DESCRIPTION

The combination, dual function Inlet Air Temperature/
Pressure Sensor (4) is located on the air cleaner (fil-
ter) cover.

OPERATION

The Inlet Air Temperature/Pressure Sensor is a combination dual-function sensor. The sensor element extends into
the intake air stream at the top of the air filter housing. Ambient air temperature as well as barometric pressure is
monitored by this sensor. The Engine Control Module (ECM) monitors signals from this sensor.

REMOVAL

The Inlet Air Temperature/Pressure Sensor is located
on the air cleaner cover.

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1. Disconnect electrical connector at sensor.

2. Remove two Torx-type mounting screws (3).

3. Remove sensor from air cleaner cover.

4. Check condition of sensor o-ring (2).

INSTALLATION

1. Check condition of sensor o-ring.

2. Position sensor into top of air cleaner cover with a slight twisting action.

3. Install 2 mounting screws.

4. Install electrical connector.

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