Replacement of elements of the EFI system (for engines 3.8LV6)


Upper intake manifold and throttle body

Note: This procedure will help replace the gasket between the upper and lower intake manifolds, as well as service the fuel rail assembly components. The procedure that follows is to replace the gasket between the throttle body and the upper intake manifold.


1. Disconnect the negative battery cable.

2. Remove the air cleaner connecting sleeve (see section 8)

3. Pull out the electrical connectors for the auxiliary air valve, throttle position sensor and EGR position sensor (see pictures).

14.3, a. Basic elements of the electronic fuel injection system (EFI). used in 3.8LV6 engines.
1. Vacuum line connector.
2.EGR valve.
3. Throttle body.
4. Front of the engine.
5. PCV valve.
6. Fuel injector.
7. Crankcase ventilation tube.
8. Fuel pressure regulator.
9. Front of the engine.
10. Throttle valve for auxiliary air.
11. Fuel injector.
12. Distributor with cover assembly.
13. View A.

4. Disconnect the throttle cable and downshift cable from the throttle connection (see section 9).

5. Carefully mark then disconnect the vacuum lines from their inlets (branches), as well as the EGR valve, fuel pressure regulator and two pipes from the corresponding tips on the throttle body.

6. Disconnect the PCV hose from the nozzle located at the rear of the upper manifold.

7. Turn off six fixing bolts of the top inlet manifold (see picture).

8. Remove the upper manifold along with the throttle body from the lower intake manifold.

9. Remove and discard the old gasket.


10. Clean and check the gasket surfaces of the upper and lower intake manifolds. When scraping off the remains of the gasket, be careful not to damage the surfaces in contact with it.

11. Place a new gasket on the sealing surface of the lower intake manifold. You can use the studs as guide pins.

12. While holding the gasket in position with the studs, install the top of the intake manifold with the throttle body onto the lower manifold.

Note: if there are no guide pins on the manifold, then when installing the upper part along with the throttle, make sure that the gasket has not moved from its place.

13. Install the six intake upper manifold mounting bolts, tighten them to the required torque.

14. Installation is carried out in the reverse order.

Throttle body

Note: If you need to service or disassemble the throttle body, and when replacing the gasket between the body and the top of the intake manifold, refer to the following procedure. If you are going to deal with any unit installed deeper than the upper intake manifold, then use the above sequence (there is no need to separate the throttle body and the upper intake manifold, they can be removed as one piece).


15. Disconnect the negative battery cable.

16. Remove the intake tube of the air cleaner housing (see section 9)

17. Pull out the electrical connectors of the throttle position sensor and the crushing valve of the additional air (see below).

18. Disconnect the throttle cable, cruise control cable (if there) and cable for shifting the gearbox to a lower gear (see section 9).

19. Turn off four nuts of fastening of the case of a throttle (see figure 14.36) Remove the throttle body.

20. Remove and discard the gasket located between the throttle body and the upper intake manifold.


21. Clean adjacent surfaces. When cleaning, be especially careful not to damage the gasket surface. and also to prevent debris from getting inside the collector.

22. Install the throttle body gasket on the four upper intake manifold studs.

23. Tighten to the required torque the nuts securing the throttle body to the manifold.

24. Installation is carried out in the reverse order of disassembly.

Secondary air valve


25. Pull out the auxiliary air valve connector (see picture).

26. Remove both bolts securing the valve.

27. Remove the valve itself and its gasket.


28. Clean adjacent surfaces of the gasket.

Note: When cleaning, be especially careful not to damage the valve, throttle body gasket surface, or drop debris into the throttle body.

29. Installation is carried out in the reverse order of disassembly.

Throttle position sensor (TR)


30. Pull out the electrical connector of the TP sensor (see figure 14.25).

31. Make a mark passing from the end of the sensor to the throttle body to make sure that the sensor is in the correct position when installed.

32. Turn off two lock screws of the gauge of provision of a throttle.

33. Remove the TP sensor.


34. Carried out in reverse disassembly sequence. Check the tightness of the TP sensor screws.

Fuel rail assembly


35. Turn off a cover of a jellied mouth of a gas tank.

36. Relieve the pressure in the fuel system (see section 2).

37. Disconnect the wire from the negative battery terminal.

38. Remove upper intake manifold and throttle body assembly (see above).

39. Pull out the fuel injector electrical connectors.

40. Disconnect the fuel transfer hose from the guide assembly using Ford's special tool for filler-spring connections (ND87L-9280-A or B) or its equivalent.

To remove the throttle position sensor, pull out the connector (WITH) and unscrew the locking screws (D - only one of them is shown).

41. Remove the four bolts (two on each side), locking the fuel rail assembly (see picture).

42. Carefully separate the guide and fuel injectors, remove them.

Note: it may be easier for you to simply remove the guide from the lower intake manifold without removing the injectors, and only then separate the injectors from the guide (see below).


43. Installing the fuel rail is done in two ways.

A) first install the injectors one by one into the lower intake manifold (see below), then put the fuel guide over them and put it on the injectors so that it stands firmly.

b) first place the injectors in the guide, position the guide with the injectors correctly in relation to the lower intake manifold, then carefully insert the injectors into their seats in the lower intake manifold.

44. Attach the fuel rail assembly to the lower intake manifold with four bolts, tighten them securely.

45. Installation is carried out in the reverse order of disassembly.

Fuel injectors


46. Remove the fuel rail assembly (see above).

47. Having pulled the guide itself apart from the nozzles, grab each nozzle by the body and pull them out, slightly rocking from side to side (see picture). If, along with the guide, the nozzles also come out, then carefully pull out the nozzles along one of the guides, swinging them from side to side (see figure 13.39).

48. Noting the position of the O-rings on the injectors, remove and discard the rings (see figure 13.48).

49. Check the washer and the plastic cap that closes the atomizer of each nozzle (see picture), may show signs of deterioration. Replace if necessary.

Note: if "cap" missing, look for it in the intake manifold.


50. Lubricate the new O-rings with a light oil (ESE - М2С39 or equivalent), and install them on the ends of each nozzle.

Note: Do not use silicone grease - it will clog the injectors.

51. With light push-and-turn movements, install the injectors into either the lower intake manifold or the fuel rail assembly (use the method that seems easiest to you).

52. Install the fuel rail assembly as described above.

53. Installation is carried out in the reverse order of disassembly.

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