- Check for active event codes that may derate engine power
- Check for intermittent diagnostic codes
- Unstable fuel supply
- Restriction in the air inlet and exhaust system
Note: If the problem only occurs under certain conditions, test the engine under those conditions. Examples of certain conditions are high engine speed, full load and engine operating temperature. Troubleshooting the symptoms under other conditions can give misleading results.
Check for Active Event Codes that may Derate Engine Power
Certain event codes may derate engine power. Connect Caterpillar Electronic Technician (ET) and check for active codes and/or for logged codes. Troubleshoot any codes that are present before continuing with this procedure.
Check for Intermittent Diagnostic Codes
Certain diagnostic codes may cause poor performance. Connect Cat ET and check for active codes and/or for logged codes. Troubleshoot any codes that are present before continuing with this procedure.
- Visually check the fuel level. Do not rely on the fuel gauge only. If necessary, add fuel. If the engine has been run out of fuel, it will be necessary to purge the air from the fuel system.
- Ensure that the fuel supply valve (if equipped) is in the full OPEN position.
- Check the fuel lines for the following problems: restrictions, collapsed lines, pinched lines and loose connections. If problems are found with the fuel lines, repair the lines and/or replace the lines.
- Prime the fuel system if any of the following procedures have been performed:
- Replacement of the fuel filters
- Service on the low pressure fuel supply circuit
- Replacement of unit injectors
- Replacement of the fuel filters
- Check the fuel tank for foreign objects which may block the fuel supply.
- Check the fuel filters.
- Check the fuel quality. Make sure that the fuel meets the requirements of Special Publication, SEBU6250, "Caterpillar Machine Fluids Recommendations ".
Restriction in the Air Inlet and Exhaust System
Ensure that the turbocharger is operating correctly. Periodic inspection and cleaning is recommended for the turbocharger compressor housing (inlet side). Refer to Systems Operation/Testing and Adjusting.
Check the air filter restriction indicator. Clean plugged air filters or replace plugged air filters.
Check the air inlet and exhaust system for restrictions and/or leaks. Refer to Systems Operation/Testing and Adjusting.