194001971 - D003 ENGINE NOT RUNNING SMOOTHLY / (IRREGULAR OPERATION)

Engine judders when car is in motion and is not efficient.
Test results
0PRELIMINARY CHECKSAll OKProblems encounteredOperation

First, check:

  • condition of the air filter;
  • status of spark plugs and leads;
  • battery correctly fastened to earth See
    See E5010 STARTING AND RECHARING		Move on to Step 1Filter element dirty, damaged or not correctly fittedReplace or restore the correct filter element fitting Op.    Op. 1048A14 AIR CLEANER FILTER ELEMENT - REPLACE.
Spark plugs dirty or damagedReplace the spark plugs Op.    Op. 5510D10 SPARK PLUGS - R+R
Spark plug leads damagedReplace spark plug leads
1CHECK USING DIAGNOSTIC EQUIPMENTAll OKProblems encounteredOperation
Connect the diagnostic test equipment (Examiner or other instruments) to the tester input.

Check:

  • that there are no faults in the engine management control unit;
  • parameter plausibility
Move on to Step 2"Fuel system" error detectedSee table    Z50 ERRORE TITOLO MISCELA
"Misfire" error detectedSee table    Z56 ERRORE SEGNALE LAMBDA A MONTE
Another error detected in the control unitContinue following the instructions for the diagnostic equipment
Parameter not consistentContinue following the instructions for the diagnostic equipment
2ROAD TEST USING DIAGNOSTIC EQUIPMENTAll OKProblems encounteredOperation
Carry out a road test reproducing the conditions in which the fault occurs, keeping the diagnostic equipment connected.

Check:

  • that there are no faults in the engine management control unit;
  • parameter plausibility
Move on to Step 3"Fuel system" error detectedSee table    Z50 ERRORE TITOLO MISCELA
"Misfire" error detectedSee table    Z56 ERRORE SEGNALE LAMBDA A MONTE
Another error detected in the control unitContinue following the instructions for the diagnostic equipment
Parameter not consistentContinue following the instructions for the diagnostic equipment
3FUEL PRESSURE CHECKAll OKProblems encounteredOperation
Check the fuel supply pressure, if necessary on the road (to reproduce the conditions in which the problem occurs) Op.    Op. 0510C10 FUEL SYSTEM - CHECK DELIVERY PRESSUREMove on to Step 4Pressure not correct: obstructions in the fuel supply pipeRemove the obstructions in the fuel pipe, replace it if necessary Op.    Op. 1040B32 FRONT FUEL DELIVERY LINE - R.R.
Pressure not correct: tank not sufficiently ventilatedRestore the tank ventilation
Pressure not correct: fuel pump electric circuit interruptedRestore fuel pump electric circuit See    See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT
Pressure not correct: petrol pump damagedReplace the petrol pump assembly Op.    Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GAUGE CONTROL - R + R
4AIR CONDITIONING SYSTEM CHECKAll OKProblems encounteredOperation
Road test the vehicle, checking that the irregular behaviour does not occur when the air conditioning is switched on or offMove on to Step 5Fault only present with the air conditioning switched onSee table    See table L010 CLIMATE CONTROL NOT COOLING
5CHECK ON CORRECT OPERATIONAll OKProblems encounteredOperation
Check that the fault is no longer presentThe fault persists: control unit defectiveReplace the control unit Op.    Op. 1056B82 INJECTION/IGNITION SYSTEM E.C.U. (ONE) - R + RSearch for the fault starting from another symptom