A method for detecting improper operation of a charge motion control device
(CMC) based on exhaust temperature is disclosed. It has been found that
when the charge motion control device is switched between two positions,
the exhaust temperature changes by as much as 100 degrees C. The expected
exhaust temperature, based on commanded charge motion control device
position and current engine operating condition, and the measured exhaust
temperature are compared to determine whether the charge motion control
device has failed to attain the desired position.
