The victim was driving near 115th Street and Vermont Avenue early Sunday morning when he was shot.
Police say his friends put him in the back seat and tried to help him as they searched for a hospital.
They also broke the glass door of a service station trying to get a clerk to call 911, but it was too late.
Officers said the friends provided conflicting details about the shooting.
The L.A. County Coroner's Office identified the victim as 22-year-old Avery Jackson Dean.
If you have information related to the case, you're asked to call the LAPD at (877) LAPD 24-7.