Ford Workshop Service and Repair Manuals

General

A Denso common rail fuel injection system is used on the 2.4L Duratorq-TDCi (Puma) diesel engine.

Within the fuel pump there is an integral fuel transfer pump which draws the fuel from the fuel tank to the fuel pump.

A fuel metering valve is located in the supply port to the high-pressure chamber of the fuel pump. The fuel metering valve varies the quantity of fuel supplied to the fuel rail and fuel injector(s), in relation to the driving conditions.

The fuel is supplied at high-pressure to the fuel rail and to the fuel injectors ready for injection. Depending on engine operating conditions, the fuel injection pressure varies between 230 bar and 1600 bar.

Fuel system pressure is measured using an FRP sensor located in the fuel rail. The FRP sensor converts the fuel system pressure into a voltage signal. This voltage signal acts as an input signal to the powertrain control module (PCM) for calculation of the fuel injection quantity.

The power train control module (PCM) calculates the time of fuel injection and the fuel injection quantity depending on various input variables. The specified quantity of fuel is injected into the respective combustion chamber through the solenoid actuated fuel injector(s). In doing so, a pre-injection and a main injection occur each time.

The excess fuel is returned to the fuel tank through the fuel return line.

Fuel pump

The fuel pump is driven directly by the timing belt.

The fuel pump has two pump elements, each offset from each other by 180 degrees.

The fuel transfer pump is incorporated into the fuel pump and is located on the drive flange. The fuel transfer pump is a cycloid type pump.

The fuel metering valve is actuated by the PCM using pulse width modulation.

Fuel rail

CAUTION:The FRP sensor must not be detached or removed from the fuel rail.

The fuel rail is made from forged steel and is retained by a support bracket located on the camshaft carrier.

The fuel is delivered by one high-pressure fuel supply line from the fuel pump to the fuel rail.

From the fuel rail, the fuel travels through the high-pressure fuel supply line(s) to the fuel injector(s).

Fuel injectors

The fuel injector(s) are located centrally on the cylinder head upper section and are attached by means of retaining clamps.

The fuel injector(s) are sealed from the combustion chamber by means of a copper sealing washer located between the fuel injector and the cylinder head. A new sealing washer must always be installed when carrying out installation work.

The fuel injectors are controlled directly by the PCM.

The fuel return line(s) are attached to the top of the fuel injector and are connected in series.

When installing new fuel injectors, the injector correction factor from the new fuel injector(s) must be recorded and uploaded using the Worldwide Diagnostic System (WDS).