3233015 - 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:

  • if there is service information on the subject
  • the condition of the air intake circuit
  • the condition of the spark plugs
  • check engine wiring earths
 Continue to Step 1 Air intake circuit faultRestore the correct operation of the intake circuit
Spark plugs not the type recommended by the manufacturerReplace the spark plugs
Earths faulty Renew the wiring See   E5030  PETROL ENGINE ELECTRONIC MANAGEMENT
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 Error in the control unit Continue following the instructions for the diagnostic equipment
Inconsistent parameterAnalyze the causes that have led to this inconsistency.
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;
  • the plausibiilty of the parameters, in particular:
  • rail pressure - rail pressure setting
  • air mass
  • injection times
  • upstream Lambda sensor voltage
 Continue to Step 3 Inconsistent parameterAnalyze the causes that have led to this inconsistency
3LOW FUEL PRESSURE CIRCUIT ROAD TESTAll OKProblems metOperation
Road test the vehicle and check the fuel supply pressure in the conditions that lead to the anomaly Continue to Step 4 Insufficient fuel pressure: pipes obstructedRemove the blockages and replace the pipes if necessary
Low fuel pressure: defective pump Replace the fuel pump assembly Op.   1040A70 
4RAIL PRESSURE SENSOR CHECKAll OKProblems metOperation
Check the operation of the rail sensor Continue to Step 5 Pressure sensor faultyReplace sensor.
5PRESSURE REGULATOR CHECKAll OKProblems metOperation
Check that the voltage regulator is working Continue to Step 6 Pressure regulator faultyReplace the pressure regulator
6HIGH PRESSURE PUMP CHECKAll OKProblems metOperation
Check the operation of the high pressure pump Continue to Step 7 High pressure pump faultyReplace high pressure pump
7IGNITION OPERATION CHECKAll OKProblems metOperation
Check the continuity/insulation of the supply circuit and the coil operation; in particular, make sure that the coil operating signal is present See   E5030  PETROL ENGINE ELECTRONIC MANAGEMENT Continue to Step 8 No supply/earth Renew the wiring See   E5030  PETROL ENGINE ELECTRONIC MANAGEMENT
No operating signal Check the wiring between the coils and the ECU and, if necessary, replace the control unit See   E5030  PETROL ENGINE ELECTRONIC MANAGEMENT
8MODULAR MANIFOLD CHECK IN ACTIVE DIAGNOSISAll OKProblems metOperation
Check the operation of the modular manifold in active diagnosis Continue to Step 9 Not workingUsing a voltmeter (graphic is best) check the modular manifold operating signal and, if necessary, replace the modular manifold solenoid valve
9PHASE TRANSFORMER CHECK IN ACTIVE DIAGNOSISAll OKProblems metOperation
Check the operation of the phase transformer in active diagnosis Continue to Step 10 Not workingUsing a voltmeter (graphic is best) check the transformer operating signal and, if necessary, replace the transformer
10CHECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisFault persists: control unit faulty Replace engine management control unit Op.   1056B82