Fault Conditions (DTC EFI-45x, EFI-543

If the ECM registers more than 0.5% misfires in 1.000 engine revolutions (2500 ignition sequences), the ECM checks whether this misfiring comes from one specific cylinder or from different cylinders. If only one cylinder exceeds the limit, DTC EFI-543 is stored first and then one of DTCs EFI-451, EFI-452, EFI-453, EFI-454 or EFI-455, depending on the cylinder. If more than one cylinder exceeds the limit DTC EFI-543 is stored with a DTC for the relevant cylinder.