The fire started in a 2 1/2 story, 25-by-75-foot frame building with the auto parts store on the first floor and residential space on the second.
The fire had also spread to a neighboring building at 3432 W. Armitage Ave. It is also a 2 1/2 story frame structure with commercial property on the first floor and residences above.
There were no early reports of injuries.
The commercial portion of both addresses belongs to Lucky's Auto Parts, according to Fire Media Affairs spokesman Quention Curtis.
A 3-11 sends 12 engines, four trucks and two tower ladders. An EMS Plan I response was also called, bringing at least five ambulances.
The fire caused the CTA to reroute the No. 73 Armitage bus around the area, according to spokeswoman Wanda Taylor. The No. 73 was being rerouted in both directions between Kimball Avenue and Pulaski Road.
The Sun-Times Media Wire contributed to this report.