BRACKET AS 9Y4254 - Caterpillar

Probable Causes
Engine speed/timing sensor(s)
Electrical connectors
Injector
Fuel supply
Air inlet restrictions
Exhaust restrictions
Accessory equipmentRecommended Actions
Engine Speed/Timing Sensor(s)
Check the calibration of the engine speed/timing sensor if a CID-FMI 261-13 Engine Timing calibration required diagnostic code is active. Refer to the calibration procedure Troubleshooting, "Engine Speed/Timing Sensor - Calibrate".Electrical Connectors
Check for the correct installation of the connectors for the Electronic Control Module (ECM) J1/P1 and/or J2/P2. Check for the correct installation of the applicable fuel injector connectors. Repair the connector and/or replace the connector. Refer to the diagnostic functional test Troubleshooting, "Inspecting Electrical Connectors".Injector
Check for active diagnostic codes that are associated with the circuits for the fuel injector. Check that the injector trim codes have been entered. Perform the "Injector Solenoid Test". Verify that the ECM is energizing all the injector solenoids. Refer to the diagnostic functional test Troubleshooting, "Injector Solenoids".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. Air inlet Restrictions
Inspect the engine air cleaner. Replace plugged air filters and/or clean the filters. Check the air inlet systems for restrictions and for leaks.Exhaust Restrictions
Check the exhaust systems for restrictions and for leaks.Accessory Equipment
Check attached accessory equipment. Ensure that the accessory equipment is not lugging down the engine.