2008 Toyota 4Runner Owners Manual - Page 531

07 12.25 Leak detection pump This pump performs fuel evaporation leakage check. This check is done approximately five hours after the engine is turned off. So you may hear sound coming from underneath the luggage compartment for several minutes. It does not indicate a malfunction. Perchlorate Material Special handling may apply, See www.dtsc.ca.gov/hazardouswaste/perchlorate. Your vehicle has components that may contain perchlorate. These components may include airbag, seat belt pretensioners, and wireless remote control batteries. viii