System to diagnose variable valve actuation malfunctions by monitoring fluid pressure in a control gallery

A system for diagnosing malfunctions in a variable valve actuation system comprising:

• a hydraulically-operated latch assembly;
• a first source of pressurized fluid;
• a hydraulic valve coupled to the first source of pressurized fluid and adapted to provide pressurized fluid through the hydraulic valve to the hydraulically-operated latch assembly;
• a gallery connecting the hydraulic valve to the hydraulically-operated latch assembly;
• a pressure transducer for measuring a hydraulic pressure in the gallery;
• and
• a control unit coupled to the hydraulic valve and the pressure transducer, adapted to:
• receive a hydraulic pressure input from the pressure transducer;
• and
• identify motion of a latch of the hydraulically-operated latch assembly in the variable valve actuation system based upon an input from the pressure transducer.

A system for diagnosing malfunctions in a variable valve actuation system comprising:

• a hydraulically-operated latch assembly;
• a hydraulic valve coupled to a first source of pressurized fluid and adapted to provide pressurized fluid through the hydraulic valve to the hydraulically-operated latch assembly;
• a pressure transducer for measuring a pressure of the pressurized fluid provided by the first source of pressurized fluid;
• and
• a control unit coupled to the hydraulic valve and the pressure transducer, adapted to:
• receive a hydraulic pressure input from the pressure transducer;
• and
• identify motion of a latch of the hydraulically-operated latch assembly in a variable valve actuation system based upon an input from the pressure transducer.