Check the intake and exhaust system, checking that there are no leakd downstream of the MAP sensor/flow meter.See Test 1072A Intake and exhaust system leakage check

Also take into account:

• blow-by circuit;
• canister circuit, checking that the valve is not stuck open;
• brake servo vacuum pipes;
• Injector O-Rings

Move onto step 2

• Renew the correct seal for the system. Replace faulty parts if necessary

Move onto step 6

Turn the key to the ON position and check the activation of the fuel pump.

Whilst the pump is activated, check that the fuel pressure is not too low

Move onto step 3

• Replace the fuel pump Op. 1040A70

Move onto step 6

• Renew or, if necessary, replace the pipes involved

End of diagnosis

• Replace the fuel pump Op. 1040A70

Move onto step 6

• Calibrate correctly.

Move onto step 6

• Restore correct connections Wiring diagram E5030 PETROL ENGINES ELECTRONIC CONTROL . If necessary, replace the fuel pump

Move onto step 6

• Replace the fuel pump Op. 1040A70

Move onto step 6

Check the mechanical seal of the injectors.

In particular, check that none of the injectors are stuck closed

Move onto step 4

• Renew the correct seal for the injectors, if necessary replace them Op. 1056B70

Move onto step 6

Check that there is no water or other substances in the tank which is contaminating the fuel.

Move onto step 5

• Clean the tank and introduce new fuel.

Move onto step 6

See table Z56 UPSTREAM LAMBDA SENSOR SIGNAL ERROR starting from Step 3

Incorrect selection of diagnostic procedure

End of diagnosis

Using the diagnostic equipment, cancel the errors in the control unit.

Road test the vehicle and check that the error does not occur again

Move onto step 7

Move onto step 7

Check that the fault is no longer present

Incorrect selection of diagnostic procedure

Incorrect selection of diagnostic procedure