Flow rate adjustment method for a turbocharger

A flow rate adjustment method for a variable geometry turbocharger (1) may include steps as follows. An adjustment apparatus (80) drives an actuator (50) to an abutment position where a power transmission member (42, 43, 53) abuts a stopper (64). The apparatus (80) acquires the abutment position opening amount based on an opening detection sensor's (50) signal. The apparatus (80) drives the actuator (50) until the detection amount attains a pre-set amount, moving the power transmission member (42, 43, 53) to a temporary control position. The apparatus (80) acquires a temporary control position flow rate. It is acquired when an adjustment gas inflow apparatus (81) causes the adjustment gas to flow into an exhaust turbine (22), and a flow rate measurement sensor (83) measures the flow rate of the adjustment gas. The apparatus (80) obtains a correction amount based on a difference between the temporary control position flow rate and a real control position flow rate, which is a proper flow rate corresponding to the pre-set amount.