Patent ID: 7567867
Filing Date: 2009-07-28
Classification: F01M,F02M,Y02T

Abstract:
1. A device for diagnosing a crankcase ventilation of an internal combustion engine, having at least two cylinder banks to which the crankcase ventilation is supplied, comprising: an actuator, whose position influences a distribution of the crankcase ventilation to the at least two cylinder banks, and in which in a first position of the actuator, a different distribution of the crankcase ventilation to the at least two cylinder banks comes about than in a second position of the actuator which differs therefrom; a switchover arrangement, together with simultaneously activated operation of the at least two cylinder banks, to switch the actuator over at least once between the two different positions; a determination arrangement to determine a characteristic variable of the internal combustion engine influenced by the crankcase ventilation for at least one of the at least two cylinder banks prior to and following the switchover operation; a specification arrangement to determine a minimum value for a change in at least one of (i) the characteristic variable of at least one of the at least two cylinder banks, and (ii) a ratio of the characteristic variable between the at least two cylinder banks for the switchover-related change in the distribution of the crankcase ventilation; and an identification arrangement to detect a malfunction of the actuator if at least one change derived from the ascertained values for the characteristic variable undershoots in quantitative terms its assigned expected value.