125000732 - Z52 LEAN FUEL SYSTEM

Results of the tests
1INTAKE AND EXHAUST SYSTEM LEAKAGE CHECKAll OKProblems metOperation
Check the intake and exhaust system visually and by listening, to check that there are no leaks downstream of the MAP sensor/flow meter.

Also take into account:

  • blow-by circuit;
  • canister circuit, checking that the valve is not stuck open;
  • brake servo vacuum pipes;
  • Injector O-Rings
Continue to Step 2There are leaksRestore the correct seal for the system. Replace faulty parts if necessaryContinue to Step 5
2PETROL PRESSURE CHECKAll OKProblems metOperation
Turn the key to MAR and check that fuel pump activates.Whilst the pump is activated, check that the fuel pressure is not too lowContinue to Step 3Low pressure: fuel filter blocked/obstructedReplace the fuel pump Op.    Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GUAGE CONTROL - R + R.Continue to Step 5
Low pressure: supply pipe restrictions/leaksRenew or, if necessary, replace the pipes involved
Low pressure: pressure regulator defectiveReplace the fuel pump Op.    Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GUAGE CONTROL - R + R.Continue to Step 5
Low pressure: pressure regulator incorrectly calibratedReplace the fuel pump Op.    Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GUAGE CONTROL - R + R.Continue to Step 5
Low pressure: electrical problem in the fuel pumpRestore correct connections See    See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT. If necessary, replace the fuel pump Op.    Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GUAGE CONTROL - R + R.Continue to Step 5
Low pressure: excess pressure valve stuck openReplace the fuel pump Op.    Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GUAGE CONTROL - R + R.Continue to Step 5
3FUEL QUALITY CHECKAll OKProblems metOperation
Check that there is no water or other substances in the tank which is contaminating the fuel.Continue to Step 4Impurities presentClean the tank Op. 1040A24and introduce new fuel.Continue to Step 5
4UPSTREAM LAMBDA SENSOR CHECKAll OKProblems metOperation
Continue according to the instructions inSee table Z56-
5ERROR 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 6The fault persists
6CHECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosis.