Methods and systems are provided for improving fuel efficiency and tailpipe emissions of a variable displacement engine. Fueling is initially disabled in cylinders selected to be deactivated while pumping air through the cylinders to an exhaust after-treatment catalyst, and then valve operation is disabled. On reactivation, if manifold vacuum is dissipated, one bank of cylinders are reactivated while the other bank is operated in DFSO with valves pumping air until manifold vacuum is reestablished.