125000733 - 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 drivingContinue to Step 1I.E. fault warning light flashingContinue according to the instructions inSee table    See table K48 I.E. FAILURE WARNING LIGHT FLASHING
1ERROR CHECKAll OKProblems metOperation
Connect the diagnostic equipment (Examiner or Examiner Plus) and record the errors and environmental parameters.Check for ''(General) Misfire'' error onlyEnd of diagnosisUpstream Lambda sensor signal error presentContinue according to the instructions inSee table    See table Z56 UPSTREAM LAMBDA SENSOR SIGNAL ERROR
Mixture strength error presentContinue according to the instructions inSee table    See table Z50 MIXTURE STRENGTH ERROR
Cylinder X misfire error presentContinue according to the instructions inSee table    See table Z54 MISFIRE ERROR IN ONE CYLINDER
General misfire error, catalyzer and/or downstream Lambda sensor signal errors only presentContinue to Step 2
Other errors are presentIdentify and eliminate the cause of the problem.Continue to Step 11
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    See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT. If necessary, replace the components involved.Continue to Step 11
3CHECK ON FUEL PRESSUREAll OKProblems metOperation
Check that the fuel system pressure is correct Op.    Op. 0510C10 FUEL SYSTEM - CHECK DELIVERY PRESSUREContinue to Step 4Pressure not correctRestore the correct pressure; if necessary, replace the faulty components.Continue to Step 11
4FUEL QUALITY CHECKAll OKProblems metOperation
Check the quality of the fuel, making sure that there is no water or other impuritiesContinue to Step 5Impurities presentClean the tank Op. 1040A24and introduce new fuel.Continue to Step 11
5SIGNAL PLAUSIBILITY CHECKAll OKProblems metOperation
Checking plausibility of the MAP/debimeter sensor signal by carrying out theContinue to Step 6The signal is not plausibleReplace the flow meter Op. 1056B09.Continue to Step 12
6INTAKE 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 7There are leaksRestore the correct seal for the exhaust system, if necessary, replace the components involved.Continue to Step 11
7Check that there are no problems with the engine. In particular, check:All OKProblems metOperation
Cylinder compression correct Op.    Op. 0510A10 CYLINDER COMPRESSION - CHECK FOR LOOSE SPARK PLUGS OR INJECTORS;Correct engine timing Op.    Op. 0510A20 TIMING GEAR WITH BELT DRIVE - CHECK - CARRY OUT OPERATION WITH CAM COVER(S) REMOVED AND TAPPETS ADJUSTED;Correct rpm sensor position;Gap between rpm sensor and flywheel within permissible limits;No visible faults on the flywheel, such as broken or chipped teethContinue to Step 8Engine timing incorrectEnsure engine timing is correct Op. 1032B14.Continue to Step 11
Rpm sensor incorrectly positionedReposition the sensor correctly.Continue to Step 11
Flywheel defectiveReplace the phonic wheel Op.    Op. 1024B60 PHONIC WHEEL ON FLYWHEEL - R R.Continue to Step 11
Compression insufficientContinue to Step 8
8CHECK 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 9Insufficient valve sealOverhaul the cylinder heads Op.    Op. 1016E26 CYLINDER HEADS - OVERHAUL.Continue to Step 11
Cylinders/piston rings wornRenew the seal.Continue to Step 11
9KINEMATIC 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 10Clutch jerkingReplace the clutch Op.    Op. 1810A20 CLUTCH - R + R.Continue to Step 11
Couplings, bearings, mountings or supports faultyReplace the components involved.Continue to Step 11
Front suspension not loadedReplace the shock absorber Op.    Op. 4410A12 FRONT SUSPENSION DAMPER (ONE), LH OR RH - FOR MCPHERSON STRUT SYSTEM - INCLUDES DISMANTLING/RE-BUILDING OF ASSEMBLY AT BENCH R R.Continue to Step 11
Wheels not balancedBalance the wheels. Replace the faulty tyres if necessaryContinue to Step 11
10INDIVIDUAL 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 according to the instructions inSee table    See table Z54 MISFIRE ERROR IN ONE CYLINDER
Error not present at a specific cylinderContinue according to the instructions inSee table    See table Z54 MISFIRE ERROR IN ONE CYLINDER
11ERROR CANCELLING AND CHECKINGAll OKProblems metOperation
Use a tester to cancel the errors in the control unit.Carry out a road test and ensure the error does not recur.Continue to Step 12The fault persists
12CHECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosis.