Two men have been released on bail after being arrested on suspicion of murder as detectives continue to investigate the killing of Jomaa Jarrare.
The 52-year-old's body was dumped in a layby near Perton and set on fire in the early hours of Monday, August 9.
Police officers made the discovery next to the Bridgnorth Road after being alerted to suspicious activity by a passing member of the public.
The road was closed for almost a week as the scene was examined.
A 56-year-old from Bilston, Wolverhampton, and a 75-year-old, from Kingstanding, Birmingham, were questioned at length by detectives but released under investigation.
A third suspect - the first to be arrested - was released facing no further action after accounting for why he had been near the scene.
The death of Ms Jarrare, who lived in Heath Town, prompted a huge appeal for information from detectives, who still want to hear from anyone with information.
It took police two days to identify Ms Jerrare, with officers initially believing the body belonged to a younger woman.
The severity of the burns to her body meant it was difficult to establish her age, gender and ethnicity.
Ms Jerrare, who was said by police to have lived a chaotic lifestyle, had not been seen by her family for six weeks or by neighbours for four weeks.
But Detective Superintendent Tom Chisholm, who is leading the investigation for Staffordshire Police, said it was not unusual for her to be out of contact for a length of time. She had not been reported missing.