The car smashed through the storefront's glass at 120 E. Sunrise Hwy. about 3:30 p.m. and pinned a customer, 45, police said.
The man who was pinned was hospitalized in serious condition with internal injuries, police said.
Two other patrons, ages 55 and 60; the driver; and his female passenger, 85, suffered minor injuries and were also taken to hospitals, police said.
Four employees in the store escaped injury, police said.
Detectives found no apparent crime, police said, and a test given at the scene did not show alcohol in the driver's breath.
The car was impounded for brake and safety checks.