Internal combustion engine comprising a variable valve lift system and a method for controlling valve lift shifting

Abstract

An internal combustion engine including a variable valve lift system whereby the engine can operate selectively in either of at least two valve lift modes, as well as a method for controlling valve lift shifting in such an engine are disclosed. The method comprises comparing the fuel supply with a fuel supply threshold value, and at least partly based on the result of the comparison, determining whether a valve lift mode shift should be performed. Preferably, the fuel supply threshold value corresponds to the fuel supply being cut off.

1 . A method for controlling valve lift shifting in an internal combustion engine having a variable valve lift system, comprising: 
 comparing an actual fuel supply with a fuel supply threshold value; and    at least partly based on the result of the comparison, determining whether a valve lift mode shift should be performed.    
   
   
       2 . The method according to  claim 1 , wherein said fuel supply threshold value corresponds to said actual fuel supply being cut off.  
   
   
       3 . An automotive system, comprising: 
 an internal combustion engine having a variable valve lift system; and    an engine control unit adapted to compare an actual engine fuel supply with a fuel supply threshold value, and at least partly based on a result of the comparison, determine whether a valve lift mode shift should be performed.    
   
   
       4 . An automotive system according to  claim 3 , wherein said fuel supply threshold value corresponds to the fuel supply being cut off.  
   
   
       5 . A method for controlling valve lift shifting in an internal combustion engine having a variable valve lift system, comprising: 
 performing a valve lift mode change when at least an actual engine fuel less is than or equal to a fuel supply threshold value; and