Note: A faulty DPF will allow some smoke to be visible. In this situation, there may not be a fault in the engine.
- Diagnostic codes
- Software in the Electronic Control Module (ECM)
- Air intake system or exhaust system
- Valve lash
- Turbochargers (if equipped)
- Low compression (cylinder pressure)
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
- Connect the electronic service tool to the diagnostic connector.
- Check for active diagnostic codes on the electronic service tool.
- 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.
- Check the display on the control panel for active diagnostic codes.
- Troubleshoot any active codes before continuing with this procedure. Refer to Troubleshooting, "Troubleshooting with a Diagnostic Code".
Use the electronic service tool to check the setup of the throttle.
- Connect the electronic service tool to the diagnostic connector and check for the following conditions:
- Check for the correct engine serial number
- Check for the correct arrangement number
- Check for the correct software
- Use the electronic service tool to verify any active diagnostic codes.
- If diagnostic codes are present, the ECM must be programmed with the correct information.
- If the repairs have not eliminated the fault, proceed to "Air Intake System or Exhaust System".
Air Intake System or Exhaust System
- Check the air filter restriction indicator, if equipped.
- Ensure that the air filter is clean and serviceable.
- Check the air intake and the exhaust system for the following defects:
- Blockages
- Restrictions
- Damage to the air intake and exhaust lines and hoses
- Make all necessary repairs to the engine.
- If the fault has not been eliminated, proceed to "Valve Lash".
Ensure that the valve lash is correct. Refer to Systems Operation, Testing, and Adjusting, "Engine Valve Lash - Inspect".
If the fault is not eliminated, proceed to "Turbocharger (If Equipped)".
Note: The turbocharger that is installed on this engine is a nonserviceable item. If any mechanical fault exists, then the faulty turbocharger must be replaced.
- Ensure that the mounting bolts for the turbocharger are tight.
- Check that the oil drain for the turbocharger is not blocked or restricted.
- Check that the compressor housing for the turbocharger is free of dirt, debris, and damage.
- Check that the turbine housing for the turbocharger is free of dirt, debris, and damage.
- Check that the turbine blades rotate freely in the turbocharger.
- Ensure that the wastegate on the turbocharger is adjusted correctly. Refer to Systems Operation, Testing, and Adjusting, "Turbocharger - Inspect". If the wastegate actuator is faulty, replace the turbocharger. Refer to Disassembly and Assembly, "Turbocharger - Remove" and Disassembly and Assembly, "Turbocharger - Install".
- If necessary, replace the turbocharger. Refer to Disassembly and Assembly, "Turbocharger - Remove" and Disassembly and Assembly, "Turbocharger - Install".
- Check that the repairs have eliminated the faults.
- If the repairs have not eliminated the fault, proceed to "Low Compression (Cylinder Pressure)".
Low Compression (Cylinder Pressure)
- Perform a compression test. Refer to Systems Operation, Testing, and Adjusting, "Compression - Test ".
- 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
- Perform all necessary repairs.
- Ensure that the repairs have eliminated the faults.
- If the repair does not eliminate the fault, contact the Technical Communicator at a Cat® dealer.