Visual Inspection

Before diagnosing or servicing the fuel injection system, perform a visual inspection for loose, disconnected, or misrouted wires and hoses. A thorough visual inspection that includes the following checks saves unnecessary test and diagnostic time.

Fig. 16 Throttle Position Sensor:

1. Inspect the throttle position sensor connector. Verify the connector is attached to the sensor (Fig. 16).
2. Inspect vacuum connections at the intake manifold for leaks (Fig. 16).

Fig. 17 Fuel Injector Electrical Connector:

3. Verify the correct electrical connector is attached to each injector (Fig. 17). Make sure the number on the tag attached to the connector corresponds with the injector.

Fig. 18 MAP Sensor. Electrical Connection:

4. Ensure the MAP sensor electrical connector is attached to the sensor (Fig. 18). Inspect the connector for damaged terminals.

Fig. 19 MAP Sensor Vacuum Connection:

- Verify the MAP sensor is connected to the vacuum nipple on the manifold (Fig. 19). Inspect the vacuum connection for damage and leaks.

Fig. 20 Heated Oxygen Sensor-Typical:

5. Check the electrical connection at the heated oxygen sensor on each exhaust manifold (Fig. 20). Inspect the connectors for damaged terminals.
6. Verify the ignition cables are connected to the spark plug cables.

Fig. 21 Idle Air Control Motor:

7. Check the electrical connection at the idle air control motor (Fig. 21).

Fig. 22 PCV Valve:

8. Inspect PCV valve hoses for leaks at the valve and intake manifold (Fig. 22).

Fig. 23 In take Air Temperature Sensor:

9. Check the electrical connection at the intake air temperature sensor (Fig. 23). Inspect the connector for damaged terminals.
10. Inspect the air filter elements in the air cleaner.

Fig. 24 Generator:

11. Inspect the electrical connections at the generator. Check for corrosion (Fig. 24).

Fig. 25 Camshaft Position Sensor:

1G12. Inspect the camshaft position sensor electrical connection for damage or corrosion (Fig. 25).

Fig. 26 Crankshaft Position Sensor:

13. Inspect the crankshaft position sensor electrical connector for damage or corrosion (Fig. 26).

Fig. 27 Starter Motor:

14. Check electrical connections at the starter motor for damage or corrosion (Fig. 27).

Fig. 28 ASD and Starter Relays:

15. Check the Auto Shutdown (ASD) and starter relays (Fig. 28).

Fig. 29 Engine Coolant Temperature Sensor:

16. Check the engine coolant temperature sensor electrical connection at the front left of the engine (Fig. 29).

Fig. 30 Ignition Colt Packs:

17. Ensure electrical connectors are inserted in ignition coils (Fig. 30).
18. Inspect battery cable connections.
19. Check the fuel pump relay connection.