C1.5 and C2.2 Engines for Caterpillar Built Machines Caterpillar

Probable Causes

• Diagnostic codes

• Accessory equipment

• Fuel supply

• Low compression (cylinder pressure)

Recommended Actions

Diagnostic Codes

Use one of the following methods to check for active diagnostic codes:

• The electronic service tool

• The display on the control panel

Electronic Service Tool

1. Connect the electronic service tool to the diagnostic connector.

2. Check for active diagnostic codes on the electronic service tool.

3. Investigate any active codes before continuing with this procedure. Refer to Troubleshooting, "Troubleshooting with a Diagnostic Code".

Display on the Control Panel

Note: The following procedure is only applicable if the application is equipped with a display on the control panel.

1. Check the display on the control panel for active diagnostic codes.

2. Troubleshoot any active codes before continuing with this procedure. Refer to Troubleshooting, "Troubleshooting with a Diagnostic Code".

Accessory Equipment

Check all accessory equipment for faults that may create excessive load on the engine. Repair any damaged components or replace any damaged components.

If there are no faults with the accessory equipment, refer to "Fuel Supply".

Fuel Supply

1. Visually check the fuel tank for fuel. The fuel gauge may be faulty.

2. Ensure that the fuel supply valve (if equipped) is in the full OPEN position.

3. If the temperature is below 0 °C (32 °F), check for solidified fuel (wax).

4. If equipped, check the water separator for water in the fuel.

5. Check for fuel supply lines that are restricted.

6. Check that the low-pressure fuel lines are tight and secured properly.

7. If equipped, replace the in-line fuel strainer and the fuel pre-filter.

8. Check that the Electric Fuel Lift Pump (EFLP) is operating. If the EFLP is suspect, refer to Troubleshooting, "Fuel Pump Relay Circuit - Test".

9. Replace the main fuel filter.

10. Check the diesel fuel for contamination. Refer to Systems Operation, Testing, and Adjusting, "Fuel Quality - Test".

11. Check for air in the fuel system. Refer to Systems Operation, Testing, and Adjusting, "Air in Fuel - Test".

12. Ensure that the fuel system has been primed. Refer to Systems Operation, Testing, and Adjusting, "Fuel System - Prime".

13. If necessary, repair any faults.

14. If there are no apparent faults, refer to "Low Compression (Cylinder Pressure)".

Low Compression (Cylinder Pressure)

1. Perform a compression test. Refer to Systems Operation, Testing, and Adjusting, "Compression - Test ".

2. If low compression is noted on any cylinders, investigate the cause and rectify the cause.

   Possible causes of low compression are shown in the following list:

   • Loose glow plugs

   • Faulty piston

   • Faulty piston rings

   • Worn cylinder bores

   • Worn valves

   • Faulty cylinder head gasket

   • Damaged cylinder head

3. Perform all necessary repairs.

4. Ensure that any repairs have eliminated the fault.

5. If the repair does not eliminate the fault, contact the Technical Communicator at a Cat® dealer.