- Fuel supply
- Electrical connectors or power supply
- Engine speed/timing sensor
- Ignition system
- Excessive load
Make sure that fuel is supplied at a sufficient pressure that is stable. Make sure that the size of the fuel line is sufficient. Inspect the fuel system for leaks.
The following conditions can cause the engine to malfunction:
- Low fuel pressure
- High fuel pressure
- Poor fuel quality
Make sure that the fuel pressure is correct. When possible, interview the operator in order to determine if fuel quality is in question. Try to determine if the source of the fuel was changed.
Inspect the fuel system components: fuel filter, gas pressure regulator, gas shutoff valve, fuel metering valve and actuator for the throttle. Verify that the system's components are operating correctly.
Replace the fuel filter, if necessary.
Electrical Connectors or Power Supply
- Check the wiring harnesses and the connectors. Inspect the connectors in the terminal box. Inspect the battery connections and the ground. Refer to Troubleshooting, "Inspecting Electrical Connectors".
- Use the Caterpillar Electronic Technician (ET) to check for a 168-02 diagnostic code. If this code is logged, proceed to Troubleshooting, "Electrical Power Supply".
- Inspect the wiring from the battery to the Electronic Control Module (ECM). Refer to the Electrical System Schematic. Inspect the wires and the power relay. Check the power and ground connections to the ECM. Refer to Troubleshooting, "Electrical Power Supply" for more information.
Make sure that the speed/timing sensor is installed correctly. See Troubleshooting, "Speed/Timing Sensor".
Make sure that the timing wheel is correctly installed.
Inspect the ignition transformers for loose connections, moisture, short circuits, and open circuits. Inspect the primary wiring and the secondary electrical connections.
Make sure that the correct transformers and spark plugs are installed. Inspect the extenders for signs or pin holes and arcing.
Maintain the spark plug according to the engine's Operation and Maintenance Manual.
Make sure that the load is not excessive. Reduce the load. If necessary, disengage the driven equipment and test the engine.