Dodge Nitro. Manual — part 673

7. Remove lockring. The module will spring up slightly when lockring is removed.

8. Remove module from fuel tank. Be careful not to bend float arm while removing.

INSTALLATION

INSTALLATION

Fig. 68: Identifying Drive Breaker, Lockring Remover/Installer 9340 & Lockring
Courtesy of CHRYSLER LLC

1. Using a new seal (gasket), position fuel pump module into opening in fuel tank.

2. Position lockring (5) over top of fuel pump module.

3. Rotate module until embossed alignment arrow points to center alignment mark. This step must be

performed to prevent float from contacting side of fuel tank.

4. Install Lockring Remover/Installer 9340 (3) to lockring.

5. Install 1/2 inch drive breaker (1) into Lockring Remover/Installer 9340 (3).

6. Tighten lockring (clockwise) until all seven notches have engaged.

7. Install fuel tank.

PUMP-FUEL INJECTION

DESCRIPTION

FUEL INJECTION PUMP

CAUTION: Whenever the fuel pump module is serviced, the rubber seal (gasket) must

be replaced.

2007 Dodge Nitro R/T

2007 ENGINE Fuel System - Nitro

Fig. 69: Identifying Fuel Injection Pump & Fuel Quantity Solenoid
Courtesy of CHRYSLER LLC

A radial, 3 piston pump (1) mounted to the timing belt cover, is used to deliver fuel under high pressure to the
fuel rail. See WARNING.

The pump is driven by the timing belt. Pressure is generated independently of the injection process. The pump
is lubricated with diesel fuel and is not responsible for fuel injection timing. However, there is a mark on the
high pressure fuel pump sprocket that must be aligned with a mark on the timing belt cover whenever the high
pressure pump, sprocket, or timing belt have been removed.

OPERATION

FUEL INJECTION PUMP

High Pressure Pumping Plungers

The fuel quantity solenoid supples three high pressure pumping chambers. The pumping chambers have one
way inlet valves that allow fuel to flow into the chambers. The valves then close during compression of the fuel
and cause the high pressure fuel to overcome a ball and angled seat outlet valve.

All three pumping chambers are tied together in one circuit internal to the pump and provide high pressure fuel
up to 1600 bar (23,000 psi) through a steel line, to the fuel rail.

The pump is driven at 1:1 engine speed and is not responsible for injection timing. The pump is only
responsible for providing high pressure fuel while the ECM controls the injection timing.

1 - FUEL INJECTION PUMP
2 - FUEL QUANTITY SOLENOID

2007 Dodge Nitro R/T

2007 ENGINE Fuel System - Nitro

REMOVAL

FUEL INJECTION PUMP

1. Disconnect negative battery cable.

2. Drain engine coolant. Refer to COOLING article .

3. Raise and support vehicle.

4. Disconnect and reposition engine coolant hose near rear of injection pump.

5. Remove timing belt.

Fig. 70: Identifying Injection Pump Sprocket Mounting Nut & Sprocket

CAUTION: Cleanliness cannot be overemphasized when handling or replacing diesel

fuel system components. 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 necessary. When installing new
parts, lubricate them with clean engine oil or clean diesel fuel only.

WARNING:

High-pressure lines deliver diesel fuel under extreme pressure from the
injection pump to the fuel injectors. Use extreme caution when inspecting
for high-pressure fuel leaks. Fuel under this amount of pressure can
penetrate skin causing personal injury or death. Inspect for high-pressure
fuel leaks with a sheet of cardboard. Wear safety goggles and adequate
protective clothing when servicing fuel system.

2007 Dodge Nitro R/T

2007 ENGINE Fuel System - Nitro

Courtesy of CHRYSLER LLC

6. Remove injection pump sprocket mounting nut (2). Attach a typical 3-jaw gear/sprocket puller such as

special tool 1023 and remove sprocket (1) from pump.

Fig. 71: Identifying High-Pressure Fuel Sensor, Electrical Connector & Fuel Lines
Courtesy of CHRYSLER LLC

7. Disconnect high-pressure fuel line (4) at rear of pump by removing banjo bolt.

8. Disconnect high-pressure fuel line (2) at rear of pump by removing fitting at end of line.

9. Disconnect electrical connector at high-pressure fuel sensor (1).

Fig. 72: Identifying Fuel Injection Pump & Fuel Quantity Solenoid

2007 Dodge Nitro R/T

2007 ENGINE Fuel System - Nitro