Nissan Armada 2025-2026 Service and Repair Manual: High Pressure Fuel Pump and Fuel Hose

Exploded View

CAUTION:

Never remove or disassemble parts unless instructed as shown in the figure.

	High pressure fuel pump insulator		High pressure fuel pump		O-ring
	High pressure fuel pump lifter		Bracket		Holder
	Fuel feed hose
	To fuel rail (bank 1). Refer to Exploded View.		To centralized under-floor piping. Refer to Hydraulic Layout.		Comply with the assembly procedure when tightening. Refer to Removal & Installation.
	: N·m (kg-m, ft-lb)
	: Always replace after every disassembly.
	: Should be lubricated with oil.

Removal & Installation

WARNING:

Jacking up or lift up the vehicle may the vehicle height to go down which cause a personal injury and/or damage to the air suspension component parts. Refer to Precaution for when Jacking and Lifting Up the vehicle with Electronic Air Suspension System.

REMOVAL

WARNING:

• Be sure to read Refer to PRECAUTION FOR HANDLING HIGH PRESSURE FUEL SYSTEM. when working on the high pressure fuel system.

• Put a “CAUTION: FLAMMABLE” sign in the workshop.

• Be sure to work in a well ventilated area and furnish workshop with a CO₂ fire extinguisher.

• Never smoke while servicing fuel system. Keep open flames and sparks away from the work area.

Release fuel pressure. Refer to Work Procedure.

Remove engine cover. Refer to Removal and Installation.

Remove air cleaner cover and air duct. Refer to Removal and Installation.

Remove air inlet tube 1. Refer to Removal & Installation.

Remove intake manifold. Refer to intake manifold : Removal and Installation.

Remove fuel tube (bank 1). Refer to Removal and Installation.

Disconnect high pressure fuel pump harness connector .

Remove high pressure fuel pump insulator .

Disconnect quick connector with the following procedure :

Disconnect fuel feed hose from holder . Disengage and pull up the pawl of the fuel feed hose connector retainer to disconnect the fuel feed hose from high pressure fuel pump.

NOTE:

If the fuel feed hose is stuck, hold the fuel pipe by hand and disconnect it by pushing and pulling.

CAUTION:

• Keep parts away from heat source. Especially, be careful when welding is performed around them.

• Never expose parts to battery electrolyte or other acids.

• Never bent or twist connection between quick connector and fuel feed hose (with damper) during installation/removal.

• Pull quick connector holding .

• Never remove the retainer.

• Prepare a tray and waste beforehand as fuel leaks out.

• Never pull with lateral force applied. O-ring inside quick connector may be damaged.

  Retainer color

  : Red

• To prevent damage to each joint and protect it from the entry of foreign matter, cover the joint with plastic bag or an equivalent.

  

Remove high pressure fuel pump and lifter.

CAUTION:

To prevent damage to high pressure fuel pump and camshaft bracket, loosen bolt alternately by one turn at a time until the reaction force applied on the high pressure fuel pump disappears.

INSTALLATION

CAUTION:

• Do not reuse O-rings.

• To prevent damage to parts due to generated abnormal stress and eccentric load, always observe the installation procedure.

Install high pressure fuel pump according to the following procedure.Check the orientation of pump cam from the mounting area (view arrow) of high pressure fuel pump.

Aim pump cam at the BDC area (arrow position).

: Camshaft (EXH)

NOTE:

For BDC area, anywhere within the area indicated by arrow can be accepted.

Install O-ring to high pressure fuel pump. When handing new O-ring, paying attention to the following caution items:

CAUTION:

• Do not reuse O-ring.

• Handle O-ring with bare hands. Never wear gloves.

• Lubricate O-ring with new engine oil.

• Never clean O-ring with solvent.

• Check that O-ring and its mating part are free of foreign material.

• Never damage O-ring with tools and fingernails during the installation. In addition, twisting or stretching O-ring is not allowed. If O-ring is stretched during the installation to high pressure fuel pump, never install high pressure fuel pump immediately.

Install high pressure fuel pump lifter. Apply oil to the fitting area of high pressure fuel pump O-ring and camshaft bracket side to install high pressure fuel pump. Install high pressure fuel pump. To prevent damage to high pressure fuel pump and camshaft bracket, the following instructions must be observed.

CAUTION:

• Temporarily tighten bolt by hand. Alternately tighten bolt by one turn at a time until high pressure fuel pump reaches camshaft bracket.

  

  : High pressure fuel pump

• After a pump flange sitting, tighten the bolts to the specified torque.

  Length of screw thread	Specified torque
  25 mm (0.98 in)	: 26.5 N·m (2.7 kg-m, 20 ft-lb)

Connect fuel feed hose with the following procedure, and them install the fuel feed hose.Check no foreign substances are deposited in and around matching pipe and quick connector, and no damage on them. Quick connector shall be inserted gradually, aligning with the axis of the matching pipe. Insert the retainer until it clicks and check the retainer is locked. After insertion, pull the connector and check that the connector is locked.

	: Lock position
	: Unlock position

CAUTION:

If retainer cannot be installed smoothly, quick connector may be have not been installed correctly. Check connection again.

After attaching the quick connector and fix the hose to the clamp.

Install in the reverse order of removal after this step.

Inspection

INSPECTION AFTER INSTALLATION

Check for Fuel Leakage

Turn ignition switch “ON” (with the engine stopped). With fuel pressure applied to fuel piping, check that there is no fuel leakage at connection points.

NOTE:

Use mirrors for checking at points out of clear sight.

Start the engine. With engine speed increased, check again that there is no fuel leakage at connection points.

CAUTION:

Never touch the engine immediately after it is stopped because the engine is extremely hot.