WASHER 4L2729 - Caterpillar

The probable root causes are listed in order below:Note: If the fault is intermittent and the fault cannot be duplicated, refer to Troubleshooting, "Intermittent Low Power or Power Cutout".Note: If the fault 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.Probable Causes
Diagnostic codes
Speed demand input
Air intake and exhaust system
Glow plugs
Valve lash
Fuel supply
Fuel rail pump
Low compression (cylinder pressure)
Individual malfunctioning cylinder
Electronic unit injectorsRecommended Actions
Diagnostic Codes
Check for active diagnostic codes on the electronic service tool. Troubleshoot any active codes before continuing with this procedure.Speed Demand Input
Use the electronic service tool and observe the signal for the Speed Demand Input.
If the signal is erratic on a genset with an EMCP3 control panel, refer to Systems Operation, Troubleshooting, Testing and Adjusting, KENR8783.
If the signal is erratic on a genset with an MCS control panel, refer to the documentation for the PWM converter.
If the repairs do not eliminate the fault proceed to "Air Intake and Exhaust System".Air Intake and Exhaust System
Check the air filter restriction indicator, if equipped.
Ensure that the air filter is clean and serviceable.
Check the air intake and exhaust systems for the following defects:
Blockages
Restrictions
Damage to lines or hoses
If the repairs do not eliminate the fault proceed to "Glow Plugs".Glow Plugs
Check for proper operation of the glow plugs. Refer to Systems Operation, Testing and Adjusting, "Glow Plugs - Test".
If the repairs do not eliminate the fault refer to "Valve Lash".Valve Lash
Check the valve lash and reset the valve lash if it is necessary. Refer to Systems Operation, Testing and Adjusting, "Engine Valve Lash - Inspect and Adjust".
If the repair does not eliminate the fault proceed to "Fuel Supply".Fuel Supply
Visually check the fuel tank for fuel. The fuel gauge may be faulty.
Ensure that the fuel supply valve (if equipped) is in the full OPEN position.
If the temperature is below 0 °C (32 °F), check for solidified fuel (wax).
Check the primary filter/water separator for water in the fuel.
Check for fuel supply lines that are restricted.
Check that the low pressure fuel lines are tight and secured properly.
Check the fuel filters.
Check the diesel fuel for contamination. Refer to Systems Operation, Testing and Adjusting, "Fuel Quality - Test".
Check for air in the fuel system. Refer to Systems Operation, Testing and Adjusting, "Air in Fuel - Test".
Ensure that the fuel system has been primed. Refer to Systems Operation, Testing and Adjusting, "Fuel System - Prime".
Check the fuel pressure. Refer to Systems Operation, Testing and Adjusting, "Fuel System Pressure - Test".
If the repair does not eliminate the fault refer to "Fuel Rail Pump".Fuel Rail Pump
Note: The fuel rail pump that is installed by the factory on the C6.6 engine is a nonserviceable item. If any mechanical fault or any electrical fault occurs within the fuel rail pump then the fuel rail pump must be replaced.
Use the electronic service tool to select the correct screen display. Refer to Troubleshooting, "Troubleshooting with a Diagnostic Code".
If the fault