RepairPal Certified shops can diagnose and repair your 2001 Toyota Sequoia. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
Evaporative Emmission control system vent control system malfunction,
Either the gas cap is leaking, or the tank has a vacuum leak within the emmission system, I would have the system smoke tested by a competant emissions shop.