3233220 - Z52 LEAN FUEL SYSTEM
-| Results of the tests | ||||
| 1 | INTAKE AND EXHAUST SYSTEM LEAKAGE CHECK | All OK | Problems met | Operation |
|---|---|---|---|---|
| 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:
| Continue to Step 2 | Leaks are present | Eliminate leaks from the system. Replace faulty parts if necessary Continue to Step 5 | |
| 2 | PETROL PRESSURE CHECK | All OK | Problems met | Operation |
| Turn the ignition on and check that the fuel pump activates.While the pump is active, check fuel pressure is not too low | Continue to Step 3 | Low pressure: fuel filter blocked/obstructed | Replace the fuel pump Op. 1040A70 Continue to Step 5 | |
| Low pressure: supply pipe restrictions/leaks | Renew or, if necessary, replace the pipes involved | |||
| Low pressure: pressure regulator defective | Replace the fuel pump Op. 1040A70 Continue to Step 5 | |||
| Low pressure: pressure regulator incorrectly calibrated | Replace the fuel pump Op. 1040A70 Continue to Step 5 | |||
| Low pressure: electrical problem in the fuel pump | Restore the correct connections See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT and if necessary replace the fuel pump Continue to Step 5 | |||
| Low pressure: pressure relief valve stuck open | Replace the fuel pump Op. 1040A70 Continue to Step 5 | |||
| 3 | CHECKING FUEL QUALITY | All OK | Problems met | Operation |
| Check that there is no water or other substances in the tank which is contaminating the fuel. | Continue to Step 4 | Impurities are present | Clean the tank and introduce new fuel Continue to Step 5 | |
| 4 | UPSTREAM LAMBDA SENSOR CHECK | All OK | Problems met | Operation |
| See table Z56 UPSTREAM LAMBDA SENSOR SIGNAL ERROR starting from Step 3 | End of diagnosis | - | ||
| 5 | DELETING AND CHECKING ERROR | All OK | Problems met | Operation |
| 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 6 | The fault persists | Continue to Step 1 | |
| 6 | CHECKING CORRECT OPERATION | All OK | Problems met | Operation |
| Check that the fault is no longer present | End of diagnosis | Fault persists | Search for the fault starting from another symptom' | |