Detectives probing the baffling discovery of a man's charred torso on a Queensland roadside have made a breakthrough.

The headless remains, with arms severed at the elbows and nothing left below the rib cage, have been identified as belonging to a 66-year-old from Teewah on the Sunshine Coast

Police say they are also questioning a 57-year-old woman in relation to the case.

The remains were found at Cedar Point, near Gympie north of Brisbane, on September 19 last year.

On Wednesday, police made a public appeal for information about an orange, gold or bronze coloured hatchback spotted in the area at the time.

They said a middle-aged Caucasian woman of medium build with blonde or brown hair was believed to have been driving the car.

AAP