An investment group has purchased Baja Fresh for $31 million. The deal comes four years after the Westlake Village-based restaurant chain was acquired by Wendy’s International. Since then, Wendy’s has revamped the management and restructured the company including the closure of about 16 stores several years ago. While Baja Fresh had a successful track record in California and some Eastern Seaboard markets the restaurants have struggled in other markets. Baja Fresh currently operates about 300 restaurants in the U.S. The deal is expected to close during the fourth quarter.