Compressor`s thrust circulating air-valve diagnosing method involves determining characteristic variable of signal of pressure sensor, comparing variable with predetermined value, and diagnosing function of valve based on comparison

摘要

The method involves evaluating a signal of a pressure sensor (6), which is upstream of a throttle in an intake manifold. A characteristic variable of the signal is determined and compared with a predetermined value. The function of a thrust circulating air-valve (13) is diagnosed based on the comparison result. A determination is made to find whether a positive time gradient of the signal is present during the diagnosis. An independent claim is also included for a device for diagnosing a thrust circulating air-valve of a compressor.