Systems and methods for turbo wastegate diagnostics

A method comprising:

• in response to an indication that a vehicle equipped to charge an onboard energy storage device via an electrical connection to an electrical grid is experiencing degradation of an engine in an engine system of the vehicle, the degradation potentially related to an issue with a wastegate coupled to an exhaust system of the engine, and further responsive to an indication that the vehicle is plugged in to the electrical grid:
• obtaining a test measurement of air flow through the engine system via activating an electric compressor positioned in an intake of the engine to direct air flow through the engine system, where the test measurement of air flow is monitored via a differential pressure sensor positioned downstream of a turbine in the exhaust system, the turbine coupled to a mechanical compressor upstream of the electric compressor;
• and
• indicating whether the wastegate is functioning as desired by comparing the test measurement of air flow to one or more baseline air flow measurements obtained under similar circumstances as the test measurement at an earlier time.

A system for a hybrid electric vehicle, comprising:

• an engine positioned in an engine system, the engine system including an intake and an exhaust system;
• an exhaust gas recirculation passage including an exhaust gas recirculation valve;
• a turbine positioned in the exhaust system, the turbine mechanically coupled to a compressor in the intake;
• a wastegate valve positioned in a wastegate passage, the wastegate passage in parallel with the turbine;
• an electric compressor positioned in the intake;
• a differential pressure sensor positioned in the exhaust system downstream of the turbine;
• and
• a controller storing instructions in non-transitory memory that, when executed cause the controller to:
• obtain a first baseline air flow through the engine system via activating the electric compressor with the wastegate valve commanded closed and indicating a difference between a first air flow and a second air flow as monitored via the differential pressure sensor, the first air flow obtained with the exhaust gas recirculation valve closed and the second air flow obtained with the exhaust gas recirculation valve open;
• obtain a second baseline air flow through the engine system via activating the electric compressor with the wastegate valve commanded open and indicating a difference between a third air flow and a fourth air flow as monitored via the differential pressure sensor, the third air flow obtained with the exhaust gas recirculation valve closed and the second air flow obtained with the exhaust gas recirculation valve open;
• and
• in response to an indication that the wastegate is potentially stuck closed, commanding open the wastegate valve and obtaining a first test measurement air flow via activating the electric compressor to determine a difference between a fifth air flow obtained with the exhaust gas recirculation valve closed and a sixth air flow obtained with the exhaust gas recirculation valve open, or in response to an indication that the wastegate is potentially stuck open, commanding the wastegate valve closed and obtaining a second test measurement air flow via activating the electric compressor to determine a difference between a seventh air flow obtained with the exhaust gas recirculation valve closed and an eighth air flow obtained with the exhaust gas recirculation valve open.