Method for determining plausibility of output signal of pressure sensor of direct-injection system of motor car internal combustion engine, involves detecting sensor failure upon comparison of calculation value with pressure value

摘要

The method involves determining current rail pressure value measured by a rail pressure sensor (139). Excitation frequency of the pressure value is determined. An injector (141-144) of an internal combustion engine (100) is controlled by the frequency. An output signal is detected from the sensor over predetermined period of time. A natural frequency of pressure oscillations from the detected signal is determined. A rail pressure calculation value is determined from the natural frequency. The calculation value is compared with the pressure value. Sensor failure is detected upon the comparison. Independent claims are also included for the following: (1) a computing unit (2) a computer program including a set of instructions to perform a method for determining plausibility of an output signal of a rail pressure sensor of a common-rail direct-injection system of an internal combustion engine (3) a machine-readable memory medium including a set of instructions to perform a method for determining plausibility of an output signal of a rail pressure sensor of a common-rail direct-injection system of an internal combustion engine.