Systems Descriptions and Components

The engine and emission control system has 4 major sub-systems: air intake system, fuel delivery system, electronic control system and emission control system.

Air intake system includes air cleaner, mass air flow sensor, throttle body, idle air control valve and intake manifold.

Fuel delivery system includes fuel pump, delivery pipe, fuel pressure regulator, fuel injectors, etc.

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

Emission control system includes EGR, EVAP and PCV systems.





1. Air cleaner
2. Intake air temp. sensor
3. Mass air flow sensor
4. Throttle body
5. Idle air control valve
6. Throttle position sensor
7. EVAP canister purge valve
8. A/C condenser fan motor through relay (if equipped)
9. Manifold differential pressure sensor
10. Blank
11. Vehicle speed sensor
12. Ignition coil assembly for No.1 and No.4 spark plugs
13. Ignition coil assembly for No.2 and No.3 spark plugs
14. Camshaft position sensor
15. Transmission range switch (sensor) (A/T)
16. A/T input speed sensor
17. A/T vehicle (output) speed sensor
18. Shift solenoid valve A (A/T)
19. Shift solenoid valve B (A/T)
20. TCC solenoid valve (A/T)
20-1. Cruise control module (if equipped)
21. ECM/PCM (Engine control module/ Powertrain control module)
22. ABS control module (if equipped)
23. A/C control module (amplifier) (if equipped)
24. Electric load (s)
- Heater blower motor (if equipped)
- Rear defogger (if equipped)
- Lighting
25. Power steering pressure switch (if equipped)
26. Stop lamp switch (A/T)
27. Power/Normal change switch (A/T)
28. O/D cut switch (A/T)
29. 4WD low switch (A/T)
30. Blank
31. Blank
32. Malfunction indicator lamp ("SERVICE ENGINE SOON" lamp)
33. "O/D OFF" lamp
34. "POWER" lamp
35. Starter
36. Clutch pedal position switch (M/T) or Park/Neutral position switch in TR switch (A/T)
37. Blank
38. Main switch
39. Main fuse
39-1. Main relay
40. Battery
41. EGR valve
42. Three way catalytic converter
42-1. Heated oxygen sensor-2 (Vehicle not equipped with WU-TWC)
42-2. Crankshaft position sensor
42-3. Heated oxygen sensor-2 (Vehicle equipped with WU-TWC)
42-4. Warm up-three way catalytic converter (if equipped)
43. Engine coolant temp. sensor
44. Fuel injectors
45. PCV valve
46. Heated oxygen sensor-1
47. Fuel pressure regulator
48. Fuel filter
49. Fuel pump with fuel level sensor
50. Tank pressure sensor
51. Tank pressure control valve
52. EVAP canister
53. Tank pressure control solenoid valve
54. EVAP canister air valve
55. Data link connector