A method for a vehicle, comprising: following a vehicle-off event, waking a powertrain control module based on a comparison of an ambient temperature and a bulk fuel temperature; and then initiating an evaporative emissions system leak test. In this way, the evaporative emission leak test may be initiated without waking the powertrain control module arbitrarily. By waking the powertrain control module and initiating the test based on ambient and bulk fuel temperatures the execution rate of the leak test can be increased.