2012 Jeep Wrangler JK Factory Service Manual 14 - Fuel System

SOLENOID, Fuel Quantity

DESCRIPTION

DESCRIPTION

The fuel quantity solenoid (2) is located in the back of the high pressure pump. The solenoid is pulse width modulated by the PCM and meters the amount of fuel that flows into the high pressure elements inside of the high pressure pump. The solenoid is also inactive during the first 30 seconds to allow maximum fuel pressure to the fuel rail during start up.

OPERATION

OPERATION

The fuel quantity solenoid is a pulse width modulated valve that controls the amount of fuel sent or delayed to the high pressure pump elements inside of the high pressure pump. The PCM determines the fuel pressure set point based on engine sensor inputs. If the actual fuel rail pressure is too low, the PCM commands the solenoid to allow more fuel to flow to the high pressure pump. This minimizes the difference between the actual fuel rail pressure reading and the set point. The PCM will also operate the solenoid, delaying fuel if the fuel rail pressure becomes to high.

The fuel quantity solenoid is commanded open by the PCM to allow the high pressure pump to build maximum pressure 1800 bar (26,106 psi) the solenoid also has fuel tank heat protection function that meters the exact amount of fuel to prevent excess heated fuel from returning to the fuel tank.

REMOVAL

REMOVAL

  1. Disconnect the negative battery cable

    2.  
  2. Remove the charge air inlet hose.

    3.  
  3. Remove nuts (8) and fuel injection pump blocker (7).

    4.  
  4. Disconnect the fuel quantity solenoid wire harness connector (1).

    5.  
  5. Remove fasteners (3) and the fuel quantity solenoid (2) from the back of the high pressure pump.

    NOTE:

    Inspect the fuel quantity solenoid and high pressure pump passage for contamination or corrosion. If contamination or corrosion is present replace the high pressure pump.


    6.  
  6. Inspect solenoid and pump for corrosion.

    7.  
  7. Install a protective cap into high pressure pump.

    8.  

INSTALLATION

INSTALLATION

  1. Install a new gasket (2) and O-ring seal (1) onto the fuel quantity solenoid (3) and lubricate the O-ring seal (1) with clean diesel fuel.

    NOTE:

    Do not allow dirt or other contaminates to enter into the high pressure pump.


    2.  
  2. Remove the protective cap from high pressure pump.

    3.  
  3. Install the fuel quantity solenoid (2) into the high pressure pump. Tighten fasteners (3) to 7 N·m (62 in. lbs.).

    4.  
  4. Connect the fuel quantity solenoid wire harness connector (1).

    5.  
  5. Install the blocker plate (7). Tighten nuts (8) to 25 N·m (18 ft. lbs.).

    6.  
  6. Install the charge air inlet hose.

    7.  
  7. Connect the negative battery cable.

    8.  
  8. Start engine and inspect for leaks.

    9.