480308 Volvo.Penta Spring

Probable Causes
Diagnostic codes, event codes, and engine derates
Engine parameters
Incorrect flash file
Throttle signal
Air inlet and exhaust system
Fuel supply
Cylinder performance
Accessory and/or parasitic loadsRecommended Actions
Diagnostic Codes, Event Codes and Derates
Certain diagnostic codes, event codes and/or derates, may cause poor performance. Connect Caterpillar Electronic Technician (ET) and check for active codes and/or for logged codes. Troubleshoot any codes that are present before continuing with this procedure.If this application supports engine derates, use Cat ET to check for logged derates. Refer to Troubleshooting, "Event Codes" for the specific events that are applicable to this application. A status screen on Cat ET will display an active derate.Engine Parameters
Verify that the correct engine parameters are being used. Refer to Troubleshooting, "Configuration Parameters" for details.Incorrect Flash File
Verify that the latest flash file is installed in the Electronic Control Module (ECM). Refer to Troubleshooting, "ECM Software - Install" for the proper procedure.Throttle Signal
Monitor the status for "Throttle Position" on Cat ET. Verify that the status for "Throttle Position" is stable and that the engine is able to reach high idle speed.Air Inlet and Exhaust System
Check the air filter restriction indicator, if equipped. Clean plugged air filters or replace plugged air filters. Refer to the Operation and Maintenance Manual.
Check the air inlet and exhaust system for restrictions and/or leaks. Refer to Systems Operation/Testing and Adjusting.
Check for proper operation of the turbocharger. Fuel Supply
Visually check the fuel level. Do not rely on the fuel gauge only. If necessary, add fuel. If the engine has been run out of fuel, prime the fuel system.
Ensure that the fuel supply valve (if equipped) is in the full OPEN position.
Check the fuel lines for the following problems: restrictions, collapsed lines, pinched lines and loose connections. If problems are found with the fuel lines, repair the lines and/or replace the lines.
Prime the fuel system if any of the following procedures have been performed:
Replacement of the fuel filters
Service on the low-pressure fuel supply circuit
Replacement of unit injectorsNote: A sight glass in the low-pressure supply line is helpful in diagnosing air in the fuel.
Check the fuel tank for foreign objects which may block the fuel supply.
Check the fuel filters.
Check the diesel fuel for contamination. Cylinder Performance
Check the valve lash and reset the valve lash, if necessary. Refer to Systems Operation/Testing and Adjusting for the procedure.
Check for correct installation of the unit injector connectors. Check for correct installation of all other applicable connectors. Refer to Troubleshooting, "Electrical Connectors - Inspect".
Perform the "Injector Solenoid Test" on Cat ET in order to determine if all of the injector solenoids are being energized by the ECM.
Perform the "Cylinder Cutout Test" on Cat ET in order to identify any injectors that might be misfiring.
If Cat ET indicates a problem, remove the electronic unit injector from the suspect cylinder. Refer to Disassembly and Assembly.
Possible causes of low compression are shown in the following list:
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 problem. Accessory and/or Parasitic Loads
Check to ensure that attached accessory equipment is not lugging down the engine.Check for any excess parasitic load on the engine.