The car was in a garage of a home on the 15000 block of Las Tunas Drive. The Los Angeles County Sheriff's Department was called to the scene at about 9:30 a.m. Thursday.
The victim has only been identified as a 63-year-old Asian woman. Investigators say the discovery was made when concerned relatives showed up at the home and called 911, fearing a kidnapping was underway.
"The family conducted the welfare check. When they found certain evidence, they called the Industry station and reported the kidnapping in progress," said Det. Mike Rossen.
The driveway of the home in question was roped off in crime scene tape, and area roads surrounding the residence were blocked off.
Investigators were seen handcuffing a man and placing him in a patrol car around 1:30 p.m. Detectives wouldn't say who the man is, but did say they have detained a "person of interest" in the case.
Sheriff's officials later said the woman's 43-year-old son was detained on a possible parole violation, but was not officially named as a suspect in the murder.
Authorities have not released the woman's name, but neighbors say they have a good idea of who she is and thought something may have been wrong Wednesday night.
"At 2 a.m., the lights were still on all the way around the house, and that was suspicious because she usually turns them off at about 11. Everybody knows the system of what goes on around here, so when something strange like that happens, you wonder," said neighbor Renny Garcia Cano.
The sheriff's department says this isn't the first time they've been called to this house.
"There's been calls from that location. It had to do with domestic issues, maybe some mental health issues," said Rossen.
If you have any information about this case, you're urged to contact Crime Stoppers at (800) 222-TIPS.
Correction: An earlier version of this story reported the victim's age as 66, and the son's age as 44.