Throttle body assembly

Removal

1 Disconnect the battery negative terminal.
2 Remove the air cleaner assembly.
3 Disconnect the wiring connector for the throttle valve actuator (see illustration).



Throttle valve actuator wiring connector (arrowed)


4 Remove the electronic control unit.
5 Slacken and remove the four bolts securing the throttle body assembly to the inlet manifold. Move the ECU mounting bracket aside, then remove the assembly and collect the sealing O-ring (see illustration).



Throttle body retaining bolts (arrowed) - shown with inlet manifold removed


Refitting

6 Refitting Is a reversal of the removal procedure, bearing in mind the following points:
a) Ensure the throttle body and inlet manifold mating surfaces are clean and dry, than fit the throttle body with a new O-ring, and securely tighten the retaining bolts.
b) Refit the electronic control unit.

Fuel rail and injectors

Removal

7 Disconnect the battery negative terminal.
8 Remove the air cleaner assembly.
9 Depressurise the fuel system.
10 Disconnect the fuel supply pipe at the quick-release connector in the centre of the fuel rail (see illustration).



Fuel supply pipe quick-release connector (arrowed)


11 Disconnect the wiring connectors at the fuel injectors. Release the Injector wiring harness from the retaining clips on the fuel rail and move the harness to one side (see illustration)



Fuel injector wiring connectors (A) harness clips (B) and fuel rail retaining bolts (C) - shown with inlet manifold removed


12 Unscrew the two bolts securing the fuel rail assembly to the inlet manifold, then carefully pull the injectors from their manifold locations. Remove the assembly from the engine and remove the injector lower O-ring seals.
13 The injectors can be removed individually from the fuel rail by extracting the relevant metal clip and easing the injector out of the rail. Remove the injector upper O-ring seals.
14 Check the electrical resistance of the injector using a multimeter and compare it with the Specifications. Note: If a faulty injector is suspected, before condemning the injector it is worth trying the effect of one of the proprietary injector-cleaning treatments.

Refitting

15 Refitting is a reversal of the removal procedure, bearing in mind the following points:
a) Renew the injector O-ring seals, and smear them with a little petroleum jelly before assembling. Take care when fitting the injectors to the fuel rail and do not press them in further than required to fit the retaining clip otherwise the O-ring seal may be damaged.
b) Ensure that the injector retaining clips are securely seated.
c) On completion check the fuel rail and injectors for fuel leaks.

Throttle valve actuator

16 The throttle valve actuator is an integral part of the throttle body and cannot be individually renewed.

Throttle potentiometer

17 The throttle potentiometer is incorporated in the throttle valve actuator and cannot be individually renewed.

Accelerator pedal potentiometer

18 The accelerator pedal potentiometer is an integral part of the accelerator pedal assembly and cannot be individually renewed.

Intake air temperature/pressure sensor

Removal

19 Disconnect the battery negative terminal.
20 Remove the air cleaner assembly.
21 Disconnect the wiring connector, then undo the retaining bolt and remove the sensor from the right-hand end of the inlet manifold (see illustration).



Disconnect the wiring connector at the intake air temperature/pressure sensor


Refitting

22 Refitting is a reversal of the removal procedure.

Crankshaft TDC sensor

Removal

25 The crankshaft TDC sensor is located adjacent to the front facing side of the crankshaft pulley.
26 Disconnect the battery negative terminal.
27 Remove the timing belt upper and lower covers.
28 Undo the bolt securing the sensor to the oil pump casing and remove the sensor from its location.

Refitting

29 Locate the sensor in position and secure with the retaining bolt.
30 Engage the sensor wiring harness with the upper and lower timing belt covers, then refit the covers.

Camshaft position sensor

Removal

32 Disconnect the battery negative terminal.
33 Remove the air cleaner assembly.
34 Disconnect the wiring connector from the camshaft position sensor located in the centre of the cylinder head extension.
35 Undo the retaining bolt and withdraw the sensor from its location.

Refitting

36 Refitting is a reversal of the removal procedure.

Acceleration sensor

Removal

37 Disconnect the battery negative terminal.
38 Disconnect the wiring connector from the acceleration sensor located adjacent to the right-hand engine mounting (see illustration).



Disconnect the wiring connector from the acceleration sensor


39 Undo the retaining bolt and remove the sensor from its location.

Refitting

40 Refitting is a reversal of the removal procedure.

Electronic control unit (ECU)

Removal

41 The electronic control unit is attached to the top of the throttle body.
42 Disconnect the battery negative terminal.
43 Remove the air cleaner assembly.
44 Rotate the wiring connector locking catches and disconnect the two wiring connectors from the top of the ECU (set illustration).



Rotate the locking catches and disconnect the two wiring connectors from the top of the ECU


45 Undo the four nuts securing the ECU to the throttle body, noting the location of the earth lead under the front left-hand nut. Fit the unit up and off the throttle body.

Refitting

46 Refitting is a reversal of the removal procedure.