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P0040

P0040

Diagnosis information - DME V8 DFI

Oxygen sensors ahead of catalytic converter interchanged

NOTE: Do not use contact spray on the oxygen sensor's plug connections as this will result in irreparable damage to the lines (blockage of reference air duct).

NOTE: Do not interchange the oxygen sensor ahead of catalytic converter with the sensor behind the catalytic converter as this will result in implausible fault entries.

Diagnostic conditions
- Lambda control active
- Driving with large and small valve travel

Possible fault causes
- Oxygen sensors ahead of catalytic converter interchanged