System and method for controlling an engine

A method for controlling pressure responsive devices in an engine, said devices varying compression ratios in a plurality of engine cylinders, said method comprising:

• supplying fluid pressure to said pressure responsive devices to change compression ratios in said cylinders;
• indicating when at least one of said devices has a deteriorated response;
• and,
• increasing said fluid pressure to said devices in response to said indication.

A method for controlling a pressure responsive device in an engine, said device varying a compression ratio in an engine cylinder, said method comprising:

• supplying a first fluid pressure pulse to said pressure responsive device to change a compression ratio in said cylinder;
• determining when said device has not changed said compression ratio of said cylinder;
• and,
• supplying a second fluid pressure pulse to said device in response of said determination, said second fluid pressure pulse having a greater amplitude then said first fluid pressure pulse.

A system for controlling a pressure responsive device in an engine, said device varying a compression ratio in an engine cylinder, said system comprising:

• a pressure control device that adjusts a fluid pressure applied to said pressure responsive device based on a first signal or a second signal;
• a sensor that generates a third signal indicative of a compression ratio of said cylinder;
• and,
• a controller operably connected to said pressure control device and said first sensor, said controller configured to generate said first signal to supply fluid pressure to said pressure responsive device to change a compression ratio in said cylinder, said controller further configured to determine when said device has a deteriorated response, said controller further configured to generate said second signal to increase said fluid pressure to said device in response to said indication.

An article of manufacture, comprising:

• a computer storage medium having a computer program encoded therein for controlling a pressure responsive device in an engine, said device varying a compression ratio in an engine cylinder, said computer storage medium comprising:
• code for supplying fluid pressure to said pressure responsive device to change a compression ratio in said cylinder;
• code for determining when said device has not changed said compression ratio of said cylinder;
• and,
• code for increasing said fluid pressure to said device to change said compression ratio in said cylinder in response to said determination.