FITTING 5P4968 - Caterpillar

Note: If this problem occurs under load, refer to the diagnostic procedure Troubleshooting, "Low Power/Poor Or No Response To Throttle".Probable Causes
Fuel supply
Derated engine
Fuel position multiplier (if applicable)
Cold mode
Throttle signal
Air inlet restriction
Exhaust restriction
Leaks in air system
Valve adjustment
Injectors
Faulty accessory equipmentRecommended Actions
Fuel Supply
Check the fuel level in the fuel tank. Ensure that adequate fuel is available for the application.Check fuel lines for the following problems: restrictions, collapse and pinched line. Repair the lines and/or replace the lines.
Check the fuel tank for foreign objects which may block the fuel supply. Check for air leaks in the suction line of the fuel pump. Prime the fuel system after you perform the following procedures:
Replacing the fuel filters
Working on the low pressure fuel supply circuit
Replacing fuel injectors
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.
Check the fuel pressure during engine operation. Check the fuel pressure after the fuel filter. Refer to the Systems Operation/Testing and Adjusting manual for the correct pressure values. If the fuel pressure is low, replace the fuel filters. If the fuel pressure is still low, check the following items: fuel transfer pump, fuel transfer pump coupling and fuel pressure regulating valve. Derate
Connect Caterpillar Electronic Technician (ET) and check for an active derate event. A derate status flag will appear on Cat ET if an active engine derate is occurring. In order to view active events, go to the "Events" menu under "Diagnostics".Fuel Position Multiplier (if applicable)
Use Cat ET to verify that the fuel position multiplier is not affecting the available fuel rack. Refer to the diagnostic procedure Troubleshooting, "Fuel Position Multiplier".Cold Mode
Use Cat ET to verify that the engine has exited cold mode. A status flag will appear if the engine is operating in cold mode. This may limit engine speed.Throttle Signal
Use Cat ET in order to monitor the status of the throttle. Observe the throttle position. Verify that the throttle position is smooth from low idle to high idle. The throttle position should reach 100 percent at high idle.Air Inlet Restriction
Replace plugged air filters and/or clean the filters. Leaks in the air inlet manifold system can lower Inlet manifold pressure.Exhaust Restriction
Check the exhaust system for restrictions and/or for leaks.Valve Adjustment
Check the valve lash setting.Injectors
Use Cat ET to determine if any active diagnostic codes are present for the injector solenoids. Perform the "Injector Solenoid Test". Observe that the injector solenoids are being energized on Cat ET. Perform the "Cylinder Cutout Test". Locate the misfiring cylinder. Refer to the diagnostic functional test Troubleshooting, "Injector Solenoids".Faulty Accessory Equipment
Check all flywheel or damper driven equipment for proper operation.