A method for recognising and using changes in the exhaust gasses emitted from an engine

摘要

A method is disclosed for recognising changes in the level of hydrogen exiting a catalytic converter 6 connected to an engine 4 and using the noted change to correct a set-point voltage used for an oxygen sensor positioned downstream from the catalytic converter 6. In this way the output signal from the downstream oxygen sensor 8 can corrected to allow for the changes in hydrogen content. The change in hydrogen content may also used to determine when the catalytic converter 6 needs to be replaced. A second oxygen sensor 7 may be placed upstream of the catalytic converter 6 and used in combination with the first oxygen sensor 8 to control the air/fuel ratio of the engine 4.