GASKET 9N0237 - Caterpillar

Probable Causes
Power supply
Engine speed/timing
Unit injectors
Fuel supply
Combustion problemsRecommended Actions
ECM Power Supply
If the electronic service tool will not communicate with the Electronic Control Module (ECM), the problem is most likely with the electrical power supply to the ECM. Refer to Troubleshooting, "Electrical Power Supply Circuit - Test".Engine Speed/Timing
Crank the engine and observe the engine speed on the status screen of the electronic service tool. If the electronic service tool indicates 0 rpm, refer to Troubleshooting, "Engine Speed/Timing Sensor Circuit - Test". Note: Upon initial cranking, the status for engine speed may indicate that the engine speed signal is abnormal. This message will be replaced with an engine speed once the ECM is able to calculate a speed from the signal.
Ensure that the timing reference gear is installed correctly. The engine will not start if the gear was installed backward. Check for proper orientation between the crankshaft and camshaft drive gears. Correct the orientation and/or replace the drive gear, if necessary. Refer to Disassembly and Assembly, "Camshaft - Remove and Install". Unit Injectors
Perform the "Injector Solenoid Test" on the electronic service tool in order to determine if all of the injector solenoids are being energized by the ECM. Refer to Troubleshooting, "Injector Solenoid Circuit - Test" for additional information.Fuel Supply
Check the fuel level.
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 pressure. Refer to Testing and Adjusting, "Fuel System Pressure - Test".
Ensure that the fuel system has been primed. Refer to Testing and Adjusting, "Fuel System - Prime".
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). Combustion Problems
Check for combustion problems.Examples of combustion problems are shown in the following list:
Outside temperatures are too cold.
Mechanical problem