Method and apparatus for detecting failure of pressure sensor in internal combustion engine

A method of detecting a failure of a pressure sensor provided in association with a cylinder of an internal combustion engine for detecting the pressure therein, said method comprising the steps of:

• detecting the pressure in said cylinder by means of said pressure sensor at a first and a second predetermined crank angle, respectively, to provide a first and a second cylinder pressure;
• setting a maximum permissible value for said first cylinder pressure and a minimum permissible value for said second cylinder pressure;
• comparing said first cylinder pressure with said maximum permissible value;
• comparing said second cylinder pressure with said minimum permissible value;
• and
• determining that a failure takes place in said pressure sensor if said first cylinder pressure exceeds said maximum permissible value or if said second cylinder pressure becomes lower than said minimum permissible value.

A method of detecting a failure of a pressure sensor provided in association with a cylinder of an internal combustion engine for detecting the pressure therein, said method comprising the steps of:

• detecting the pressure in said cylinder by means of said pressure sensor at a first and a second predetermined crank angle, respectively, to provide a first and a second cylinder pressure;
• determining a difference between said first and second cylinder pressures;
• setting a threshold value as a reference for said difference;
• comparing said difference with said threshold;
• and
• determining that said pressure sensor suffers from a failure if said difference is less than said threshold value.

A method of detecting a failure of a pressure sensor provided in association with a cylinder of an internal combustion engine for detecting the pressure therein, said method comprising the steps of:

• detecting the pressure in said cylinder by means of said pressure sensor on a power stroke of said cylinder to provide a cylinder pressure;
• detecting a peak crank angle corresponding to a peak value of said cylinder pressure;
• determining peak position information on the basis of said peak crank angle;
• setting a maximum permissible value and a minimum permissible value for said peak position information;
• comparing said peak position information with said maximum permissible value;
• comparing said peak position information with said minimum permissible value;
• and
• determining that said pressure sensor suffers from a failure if said peak position information is above said maximum permissible value or if said peak position information is below said minimum permissible value.

A method of controlling the operation of an internal combustion engine in response to occurrence of a failure in a pressure sensor provided in association with a cylinder of said engine, said method comprising the steps of:

• determining whether a failure has occurred in said pressure sensor on the basis of the pressure in said cylinder detected by said pressure sensor;
• fixing an engine control parameter if it is determined that a failure has occurred in said pressure sensor;
• determining whether said failure is a mechanical failure;
• and
• stopping the control of said cylinder if said failure is determined to be the mechanical failure.