Fuel Charging System & Engine Controls: Other Ford Focus II

Sequential Multiport Fuel Injection (SFI)

The fuel charging and controls system consists of the

1. throttle body.
2. fuel injectors.
3. fuel rail.
4. fuel pump driver module (FPDM).

The fuel charging and controls system is

1. a sequential multiport fuel injection (SFI) system.
2. pulse width modulated.
3. mass air flow-controlled.

Fuel is metered into each intake port in a sequential firing order. Fuel injectors pulse to follow engine firing order, in accordance with engine demand on a tuned intake manifold.

The basic fuel requirement of the engine is determined from the data supplied to the powertrain control module (PCM) by the mass air flow (MAF) sensor, which measures the amount of air being drawn into the engine.

The various sensors detect any changes in the operating conditions and send signals to the PCM. This permits the PCM to control the opening duration (pulse width) of the fuel injectors and maintain optimum exhaust emission control and engine performance for all operating conditions.

Throttle Body

The throttle body

1. controls throttle position by a conventional cable through throttle linkage.
2. controls air supply to the intake manifold by positioning the throttle plate.
3. is not adjustable.
4. cannot be cleaned.

For additional information, refer to THROTTLE BODY in this section.

Fuel Injectors

The fuel injectors

1. are electronically operated by the PCM.
2. atomize the fuel as the fuel is delivered.
3. each have an internal solenoid that opens a needle valve, which injects fuel into the intake port in the cylinder head.
4. are deposit resistant.

For removal and installation, refer to FUEL RAIL .

Fuel Rail

The fuel rail

1. receives fuel from the fuel supply tube.
2. delivers fuel to the fuel injectors.

For removal and installation, refer to FUEL RAIL .

Fuel Pump Driver Module (FPDM)

The fuel pump driver module (FPDM)

1. receives signals from the PCM.
2. duty cycles the fuel pump.

The fuel pump relay engages the fuel pump when energized by the PCM through the FPDM.

For removal and installation, refer to FUEL PUMP DRIVER MODULE (FPDM) .

Fuel Charging and Controls

Refer to the INTRODUCTION - GASOLINE article.

Scheme 1

Scheme 2

Scheme 3

1. Disconnect the battery ground cable. For additional information, refer to «BATTERY MOUNTING AND CABLES»(ref-255404) .
2. Remove the air cleaner outlet pipe. Disconnect the crankcase breather tube. Loosen the clamps. Remove the air cleaner outlet pipe. To install, tighten the clamps to 4 Nm (35 lb-in).
3. Remove the accelerator control snow shield. Remove the upper snow shield screw and pin-type retainer. To install, tighten to 10 Nm (89 lb-in).
4. Detach the accelerator and speed control cable (if equipped) from the throttle body.
5. Disconnect the throttle position (TP) sensor electrical connector.
6. Remove the 4 bolts and the throttle body. Inspect the throttle body gasket and install new as necessary. To install, tighten to 10 Nm (89 lb-in) in the sequence shown.
7. To install, reverse the removal procedure.

Scheme 4

1. Disconnect the battery ground cable. For additional information, refer to «BATTERY MOUNTING AND CABLES»(ref-255404) .
2. Pull up the rear seat.
3. Position the floor covering to one side.
4. Disconnect the fuel pump driver module (FPDM) electrical connector.
5. Remove the 2 nuts and the FPDM. To install, tighten to 5 Nm (44 lb-in).
6. To install, reverse the removal procedure.

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Scheme 11

Scheme 12

Scheme 13

Scheme 14

Scheme 15

Scheme 16

1. Disconnect the battery ground cable. For additional information, refer to «BATTERY MOUNTING AND CABLES»(ref-255404) .
2. Disconnect the fuel pressure and temperature sensor and the 16-pin fuel charging wiring harness electrical connectors. Detach the harness from the retainer clip.
3. Detach the cylinder head temperature (CHT) sensor boot.
4. Disconnect the CHT sensor electrical connector.
5. Disconnect the electrical connectors from the ignition coils, the fuel injectors and the camshaft position (CMP) sensor. Detach the 2 wiring retainers from the valve cover stud bolts.
6. Disconnect the idle air control (IAC) motor electrical connector.
7. Disconnect the throttle position (TP) sensor electrical connector and detach the retaining clip.
8. Disconnect the 16-pin fuel charge harness electrical connector.
9. Disconnect the radio ignition interference capacitor electrical connector.
10. Disconnect the heated oxygen (HO2S) sensor electrical connector and detach the pin-type retainer.
11. Remove the generator cooling pipe.
12. Disconnect the generator electrical connector, release the wiring retainer and remove the fuel charging wiring harness.
13. To install, reverse the removal procedure.

MATERIAL CHART

Scheme 17

Scheme 18

1. Disconnect the fuel tube quick release coupling from the fuel rail and position the tube aside. For additional information, refer to «FUEL SYSTEM-GENERAL INFORMATION»(ref-255426) .
2. Disconnect the battery ground cable. For additional information, refer to «BATTERY MOUNTING AND CABLES»(ref-255404) .
3. Disconnect the 4 fuel injector electrical connectors.
4. Disconnect the fuel rail pressure and temperature sensor electrical connector and vacuum tube.
5. Remove the 2 bolts and the fuel rail and injectors. To install, tighten to 25 Nm (18 lb-ft).
6. If necessary, remove the fuel injector retaining clips and the fuel injectors. Remove and discard the O-ring seals.
7. To install, reverse the removal procedure.