2888337 - D10 ENGINE IDLE IRREGULAR

The engine is not running smoothly when idling; in particular, it does not maintain a constant, regular value as the load varies (e.g. when electrical devices are switched on, etc.).
Results of the tests
1CHECKING WITH DIAGNOSTIC EQUIPMENTAll OKProblems metOperation
Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket

Check

  • that there are no faults in the engine management control unit
  • the plausibility of all the parameters.
Continue to Step 2An error is detected in the control unit Continue according to the instructions for the diagnostic equipment
Lack of dialogue with the control unitRestore the connection between the engine management control unit and the diagnostic connector See     E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT
2CHECK ON FUEL FILTERAll OKProblems metOperation
Check the operation of the fuel filterContinue to Step 3Presence of water, petrol, paraffin or dirt detectedClean the tank and pipes and replace the filter element Op.     1044B20
3CHECKING AIR CIRCUITAll OKProblems metOperation

Check, in order:

  • the condition of the air filter
  • the condition and seal of the air supply circuit
Continue to Step 4Filter dirty or partially blockedReplace the air filter Op.     1048A14
Circuit component damagedReplace the component (see Assembly 1048A)
4VALVE CLEARANCE CHECKAll OKProblems metOperation
Check that the valve tappet clearance is correct. Op.     1036H14 Continue to Step 5Clearance not correctRestore the correct valve clearance. Op.     1036H18
5CHECK ON CYLINDER COMPRESSIONAll OKProblems metOperation
Carry out the cylinder compression test Op.     0510A10 Continue to Step 6Compression values not correctRestore the correct cylinder compression, e.g by checking the injector seal Op.     1060F10
6CHECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisFault persistsSearch for the fault starting from another symptom