SEAL-O-RING 4862241 - Caterpillar

Probable Causes
Note: If the problem is intermittent and the problem can not be duplicated, refer to Troubleshooting, "Intermittent Low Power or Power Cutout".
Malfunction of an individual cylinder
Fuel supply
Injection actuation pressure
Accelerator pedal position sensor
Power train data link
Valve lashRecommended Repairs
Perform the following diagnostic procedures in order:Note: If the problem only occurs under certain conditions, test the engine under those conditions. Examples of certain conditions are high rpm, full load and engine operating temperature. Troubleshooting the symptoms under other conditions can give misleading results.Malfunction of an Individual Cylinder
Check for a malfunction of an individual cylinder.
Ensure that the unit injector connectors are fully connected and free of corrosion.
Ensure that the J2/P2 connector for the Engine Control Module (ECM) is fully connected and ensure that the J2/P2 connector for the ECM is free of corrosion.
Connect Caterpillar Electronic Technician (ET) to the service tool connector. Access the "Cylinder Cutout Test" in the "Diagnostic Tests" under the "Diagnostic" menu. Start the "Cylinder Cutout Test" in order to test the injectors. Disabling each injector allows the technician to isolate the misfiring cylinder. If the misfiring cylinder can be isolated to a specific injector, refer to Troubleshooting, "Injector Solenoid Circuit - Test".Fuel Supply
Monitor the exhaust for smoke while the engine is being cranked. If no smoke is present, there may be a problem with the fuel quality or there may be a problem with the fuel supply.
Check the fuel quality. For further information, refer to Operation and Maintenance Manual, SEBU6385, "Caterpillar On-Highway Diesel Truck Engine Fluid Recommendations".
Check the fuel pressure. Refer to Testing and Adjusting, "Fuel System".
Ensure that the fuel system has been primed. Refer to Testing and Adjusting, "Fuel System".
Check for fuel supply lines that are restricted.
Check the fuel filters.
If the temperature is below 0 °C (32 °F), check for solidified fuel (wax).
Check for air in the fuel system. Refer to Testing and Adjusting, "Fuel System". Injection Actuation Pressure
Ensure that the injection actuation system is operating properly. Refer to Troubleshooting, "Injection Actuation Pressure - Test". Accelerator Pedal Position Sensor
If the engine is in the cruise control mode and the problem does not occur, check the accelerator pedal position sensor.
Use the "Cruise/Idle On/Off Switch" to put the engine in idle mode.
Vary the engine rpm with the set/resume switches. If both of the following conditions are met, connect Cat ET and monitor the status of the accelerator pedal position sensor.
The engine is stable by using idle mode to control the engine rpm.
The engine is unstable by using the accelerator pedal position sensor.If the status of the accelerator pedal position sensor is unstable, refer to Troubleshooting, "Accelerator Pedal (Throttle) Position Sensor Circuit - Test".Power Train Data Link
Check the power train data link. Ensure that the power train data link is not limiting the power.
Connect Cat ET to the service tool connector.
Monitor the "Power Train Data Link" status screen while the vehicle is experiencing problems. If the "Power Train Data Link" status screen indicates that the data link is limiting the power or the rpm, verify that this is not