Methods and systems are provided for progressively opening and controlling each of a fuel vapor canister purge valve (CPV), an auxiliary throttle coupled in series with a venturi, and a main intake throttle arranged in parallel with the auxiliary throttle in order to deliver a desired intake airflow or manifold vacuum to an engine intake manifold. In one example, a method may include actuating a CPV to supply airflow to the engine via a fuel vapor canister while holding closed a main throttle and an auxiliary throttle arranged in parallel with the main throttle and in series with a venturi. The method further includes progressively opening the CPV, then the auxiliary throttle, and then the main throttle to achieve a desired intake manifold pressure.