0377943 JOHNSON GEAR, Throttle control, and shaft, long

Probable Causes
Diagnostic codes, event codes and derates
Parameters
Air inlet and exhaust system
Low pressure fuel system
High pressure fuel system
Cylinder performanceRecommended Actions
Diagnostic Codes, Event Codes and Derates
Certain diagnostic codes, event codes and/or derates may cause poor performance. 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.Note: Although a sensor's signal may be in the operational range of the sensor, certain failure modes of a sensor may produce an output signal that does not represent an accurate measurement. Use Cat ET to check that the pressures and the temperatures are fluctuating normally. Also check that the values are reasonable for the conditions that are present.Parameters
Verify that the correct engine parameters are being used.Air Inlet and Exhaust System
Check the air filter restriction indicator, if equipped. Clean plugged air filters or replace plugged air filters. Refer to the Operation and Maintenance Manual.
Check the air inlet and exhaust system for restrictions and/or leaks. Refer to Systems Operation/Testing and Adjusting. Low Pressure Fuel System
Visually check the fuel level in the fuel tank. Do not rely on the fuel gauge only. If necessary, add fuel to the fuel tank. If the engine has been run out of fuel, it will be necessary to prime the fuel system. Refer to Systems Operation/Testing and Adjusting, "Fuel System - Prime".
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.
Contact with high pressure fuel may cause fluid penetration and burn hazards. High pressure fuel spray may cause a fire hazard. Failure to follow these inspection, maintenance and service instructions may cause personal injury or death.
Do not loosen any high pressure fuel lines when the engine is running. The high pressure in the fuel lines can cause personal injury or death. Wait 60 seconds after the engine has stopped to allow pressure to purge before any service or repair is performed on the engine fuel lines.
Check the fuel lines for the following problems: restrictions, collapsed lines and pinched lines. If problems are found with the fuel lines replace the lines.
Check the fuel tank for debris or foreign objects which may block the fuel supply.
Check the fuel pressure during engine cranking. Check the filtered fuel pressure. Refer to Systems Operation/Testing and Adjusting, "Fuel System Pressure - Test".
Check fuel quality. Refer to Systems Operation/Testing and Adjusting, "Fuel Quality - Test". High Pressure Fuel System
Inspect the high pressure fuel system. Check the following components:
High pressure fuel pump
Fuel rail
Fuel linesDisconnect each harness connector from the high pressure fuel pump. Look for fuel on the connectors.If there is fuel in the connectors, clean the connectors. Having clean connectors will help ensure a good connection.Use Cat ET to perform the "Injector Solenoid Test" in order to determine if all of the injector solenoids are being energized by the ECM.Perform the "Cylinder Cutout Test" on Cat ET in order to identify any injectors that might be misfiring.Perform the "Fuel System Functional Test". Cat ET will display an error message that indicates the problem. Follow the repair procedure for the error message:"Fuel Pump Not Timed Correctly" - Remove the high pressure fuel pump and install the high pressure fuel pump. Then, run the "Fuel System Functional Test" in order to verify that the pump is timed correctly."Fuel Pump Flow Too Low" - Replace the high pressure fuel pump. Then, run the "Fuel System Functional Test" again in order to verify that the problem is resolved."Fuel Rail High Pressure Decay Too High" - Replace the pressure relief valve. Then, run the "Fuel System Functional Test" again in order to verify that the problem is resolved. If the problem is not resolved, refer to Systems Operation/Testing and Adjusting, "High Pressure Fuel Bypass - Test"."Fuel Rail Low Pressure Decay Too High" - Refer to Systems Operation/Testing and Adjusting, "High Pressure Fuel Bypass - Test".