Method for diagnosing guide probe fitted downstream from catalytic converter in system for controlling engine, involves detecting oxygen content in exhaust system for an internal combustion engine.

摘要

Test values and a guide probe are compared with preset comparison values. If the test values on the guide probe resulting from the controlling behavior of a mixture are regarded not to have reached a target, changes are deliberately made in the composition of the mixture and updated test values resulting from that are measured for the guide probe.