System Operation

EFI System:

The Electronic Fuel Injection system in this vehicle supplies the combustion chambers with air/fuel mixture of optimized ratio under widely varying driving conditions.

It uses the single-point throttle body fuel injection system which injects fuel into the throttle body through one injector.


This system has 2 major sub-systems: air/fuel delivery system and electronic control system. Air/fuel delivery system includes fuel pump, throttle body, etc..

Electronic control system includes ECM, various sensors and controlled devices.


This section explains not only the system related to the electronic fuel injection but also such functions of ECM as listed below.


- EGR control system.

- Throttle opener control system.

- ESA (Electronic Spark Advance) system.


NUMBERED COMPONENTS IN ILLUSTRATION
1. Oxygen sensor
2. Exhaust manifold
3. PCV valve
4. Intake manifold
5. Three way catalyst
6. Charcoal canister
7. To fuel tank
8. ATS
9. Fuel pressure regulator
10. Fuel injector
11. TPS
12. BVSV
13. WTS
14. Throttle body
15. ISO solenoid valve
16. Air cleaner
17. Filter
18. EGR valve
19. REGTS (California Spec. model only)
20. EGR modulator
21. EGR VSV (Blue)
22. Pressure sensor
23. Throttle opener VSV (Brown)
24. Throttle opener
25. A/C VSV (if equipped)
26. A/C amplifier (if equipped)
27. Clutch switch
28. Starter magnetic switch
29. Main relay
30. Fuel pump relay
31. Main switch
32. Battery
33. "CHECK ENGINE" light
34. Cancel switch (Federal Spec. model)
35. Mileage sensor (except California)
36. Fuel pump
37. ECM
38. Monitor connector
39. 5th switch (Not for California Spec. model)
40. Igniter
41. VSS
42. CAS