3022580 - D02 ENGINE NOT RUNNING SMOOTHLY / (LOSING POWER)

Under conditions of constant load and speed, there are intermittent decreases in performance, even prolonged
Results of the tests
0PRELIMINARY CHECKSAll OKProblems metOperation

Preliminarily check:

  • the state of the spark plugs and leads;
  • the condition of air filter
  • the condition of the air intake circuit
  • absence of obstructions in the catalytic converter
Continue to Step 1Spark plugs dirty or damagedReplace the spark plugs Op.   5510D10 
Spark plug leads damagedReplace the spark plug leads Op. 5510D14
Air intake circuit faultEliminate the problem
Catalyzer obstructedReplace the exhaust manifold Op.   1072C12 
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;
  • plausibility of all the parameters
Continue to Step 2'Supply system' error detected See table   Z50  MIXTURE STRENGTH ERROR
'Misfire' error detected See table   Z53  MISFIRE ERROR
Another error dectected in the control unitContinue following the instructions for the diagnostic equipment
Inconsistent parameterContinue following the instructions for the diagnostic equipment
2ROAD TEST WITH DIAGNOSTIC EQUIPMENTAll OKProblems metOperation
Road test the vehicle, reproducing the conditions in which the fault arises, keeping the diagnostic equipment connected.

Check:

  • that there are no faults in the engine management control unit;
  • plausibility of all the parameters
Continue to Step 3'Supply system' error detected See table   Z50  MIXTURE STRENGTH ERROR
'Misfire' error detected See table   Z53  MISFIRE ERROR
Another error dectected in the control unitContinue following the instructions for the diagnostic equipment
Inconsistent parameterContinue following the instructions for the diagnostic equipment
3FUEL PRESSURE ROAD TESTAll OKProblems metOperation
Road test the vehicle and check the fuel supply pressure Op.   0510C10  in the conditions that lead to the anomalyContinue to Step 4Insufficient fuel pressure: pipes obstructedRemove restrictions
Insufficient fuel pressure: valve obstructedReplace the tank cap Op.   1040A40 
Insufficient fuel pressure: regulator out of calibrationReplace the pump assembly Op.   1040A70 
Low fuel pressure: defective pumpReplace the pump assembly Op.   1040A70 
Low fuel pressure: clogged filterReplace the pump assembly Op.   1040A70 
4CHECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer present Fault persists: control unit defectiveReplace control unit Op.   1056B82  Search for the fault starting from another symptom'