2398916 - Z53 MISFIRE ERROR

The diagnostic equipment signals the following error: Misfire
Results of the tests
0PRELIMINARY CHECKSAll OKProblems metOperation
Visually check on the instrument panel that the MIL warning light is not flashing while the car is driving Continue to Step 1I.E. fault warning light flashingContinue according to the instructions See table   K48  I.E. FAILURE WARNING LIGHT FLASHING
1CHECK ERRORAll OKProblems metOperation
Connect the diagnostic equipment (Examiner or Examiner Plus) and record the errors and environmental parameters. Connect the diagnostic equipment (Examiner or Examiner Plus) and record the errors and environmental parameters.End of diagnosisThe 'Upstream Lambda signal' error is presentContinue according to the instructions See table   Z56  UPSTREAM LAMBDA SENSOR SIGNAL ERROR
The 'Mixture strength' error is presentContinue according to the instructions See table   Z50  MIXTURE STRENGTH ERROR
The 'Misifre in cylinder X' error is presentContinue according to the instructions See table   Z54  MISFIRE ERROR IN ONE CYLINDER
The '(General) Misfire', 'Catalyzer and/or 'Downstream Lambda signal' errors only are presentContinue to Step 2
Other errors are presentIdentify and eliminate the cause of the anomaly.Continue to Step 10
2CONTROL UNIT CIRCUIT CHECKAll OKProblems metOperation
Visually inspect the condition of the engine management control unit wiring, connections and earth.There should be no faultsContinue to Step 3Faults in the control unit electrical circuitRestore the correct connections See   E5030  PETROL ENGINE ELECTRONIC MANAGEMENT If necessary, replace the components involved.Continue to Step 10
3CHECK ON FUEL PRESSUREAll OKProblems metOperation
Check that the fuel system pressure is correct Op.   0510C10  Continue to Step 4Pressure not correctRestore the correct pressure; if necessary, replace the faulty components.Continue to Step 10
4FUEL QUALITY CHECKAll OKProblems metOperation
Check the quality of the fuel, making sure that there is no water or other impuritiesContinue to Step 5Impurities are presentClean the tank Op. 1040A24and introduce new fuel.Continue to Step 10
5INTAKE AND EXHAUST SYSTEM LEAKAGE CHECKAll OKProblems metOperation

Check the exhaust system visually and by listening. In particular, check that there are no leaks downstream of the MAP/flow meter sensor, also taking into consideration:

  • Blow-by;
  • Canister circuit;
  • Brake servo vacuum pipes;
  • Injector O-Rings
Continue to Step 6There are leaksRestore the correct seal for the exhaust system, if necessary, replace the components involved.Continue to Step 10
6ENGINE PROBLEMS CHECKAll OKProblems metOperation

Check that there are no problems with the engine. In particular, check:

  • correct cylinder compression Op.   0510A10 
  • correct engine timing
  • correct rpm sensor position
  • gap between rpm sensor and flywheel within permissible limits
  • no visible faults on the flywheel, such as broken or chipped teeth
Continue to Step 7Engine timing incorrectEnsure engine timing is correct Op.   1032B10  Continue to Step 10
Rpm sensor incorrectly positionedReposition the sensor correctly.Continue to Step 10
Phonic wheel defectiveReplace the phonic wheel Op. 1024A28Continue to Step 10
Compression insufficientContinue to Step 7
7CHECK ON CAUSE OF INSUFFICIENT COMPRESSIONAll OKProblems metOperation
Carry out R/R on head to check the valve sealCheck the condition of the cylinders/piston ringsContinue to Step 8Insufficient valve sealOverhaul the cylinder head Op.   1016E10  Continue to Step 10
Cylinders/piston rings wornRenew the seal.Continue to Step 10
8KINEMATIC MECHANISM CHECKSAll OKProblems metOperation
Check that the kinematic mechanism is not oscillating by road testing the vehicle.

In particular:

  • clutch not jerking;
  • couplings/bearings not faulty;
  • engine mountings and supports not faulty;
  • suspension loading correct;
  • wheel balancing correct
Continue to Step 9Clutch jerkingReplace the clutch Op.   1810A20  Continue to Step 10
Couplings, bearings, mountings or supports faultyReplace the components involved. Continue to Step 10
Front suspension not loadedReplace the shock absorber Op.   4410A12  Continue to Step 10
Wheels not balancedBalance the wheels Op. 4450A70Replace the faulty tyres if necessaryContinue to Step 10
9INDIVIDUAL CYLINDER ERROR CHECKAll OKProblems metOperation
Connect the diagnostic equipment (Examiner or Examiner Plus) Check for the presence of 'Misfire at cylinder X' errorEnd of diagnosisError present in at least 1 cylinderContinue as instructed in the Table See table   Z54  MISFIRE ERROR IN ONE CYLINDER referring to the cylinders concerned
Error not present at a specific cylinderContinue as instructed in the Table See table   Z54  MISFIRE ERROR IN ONE CYLINDER referring to all the cylinders in succession
10ERROR CANCELLING AND CHECKINGAll OKProblems metOperation
Use a tester to cancel the errors in the control unit. Road test the vehicle and check that the error does not occur againContinue to Step 11The fault persistsContinue to Step 0
11CHECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosis