Posted on December 1, 2020 3176C, 3406E and 3456 Industrial Engines Troubleshooting – Fuel Pressure Problem Use this procedure in order to troubleshoot low fuel pressure or use this procedure if one of the following event codes is active. Refer to Troubleshooting, “Event Codes” for information about event codes and the default trip points for these codes. You must access the monitoring system on Caterpillar Electronic Technician (ET) in order to view the current trip points for these codes. Table 1 Diagnostic Codes Table Description Conditions which Activate the Code System Response E053-1 Low Fuel Pressure Warning The fuel supply pressure is low. The code is logged. 94-1 Low Fuel Pressure Warning The fuel supply pressure is low. The code is logged. The diagnostic lamp will flash. The alarm lamp will illuminate. Probable Causes Low fuel level Partially open fuel supply valve (if equipped) Fuel lines Air in fuel Blockage in fuel tank Fuel filters Recommended Repairs Fuel Supply 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. Refer to the Operation and Maintenance Manual. 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 Note: A sight glass in the low pressure supply line is helpful in diagnosing air in the fuel. Refer to Systems Operation/Testing and Adjusting. Check the fuel tank for foreign objects which may block the fuel supply. Check the fuel filters. Check the diesel fuel for contamination. Refer to Systems Operation/Testing and Adjusting. Cold weather adversely affects the characteristics of the fuel. Refer to the Operation and Maintenance Manual for information on improving the characteristics of the fuel during cold weather operation.
