Abstract: Diagnostic systems and methods for a surge valve that selectively bypasses a compressor of a turbocharger of an engine involve receiving, by a controller, a barometric pressure signal indicative of a barometric pressure external to the engine, receiving, by the controller, a throttle inlet pressure (TIP) signal indicative of an air pressure at an inlet of a throttle valve of the engine and downstream from the surge valve and the compressor, and performing, by the controller, a diagnostic technique on the surge valve, the diagnostic technique comprising generating a pressure ratio signal that is a ratio of the TIP signal to the barometric pressure signal, applying a high-pass filter to the pressure ratio signal to obtain a filtered pressure ratio signal, and based on a quantity of detected pulses in the filtered pressure ratio signal that exceed the diagnostic threshold, detecting a malfunction of the surge valve.

Abstract: Diagnostic systems and methods for a surge valve that selectively bypasses a compressor of a turbocharger of an engine involve receiving, by a controller, a barometric pressure signal indicative of a barometric pressure external to the engine, receiving, by the controller, a throttle inlet pressure (TIP) signal indicative of an air pressure at an inlet of a throttle valve of the engine and downstream from the surge valve and the compressor, and performing, by the controller, a diagnostic technique on the surge valve, the diagnostic technique comprising generating a pressure ratio signal that is a ratio of the TIP signal to the barometric pressure signal, applying a high-pass filter to the pressure ratio signal to obtain a filtered pressure ratio signal, and based on a quantity of detected pulses in the filtered pressure ratio signal that exceed the diagnostic threshold, detecting a malfunction of the surge valve.