The L.A. County Sheriff's Dept. has almost cracked a murder case involving YG's vehicle, and now they're asking for the public's help in solving the mystery.
TMZ broke the story back in July ... his SUV was involved in a high-speed chase through the streets of L.A. that ended in a deadly police shootout.
Police were originally called to apprehend a reckless DUI suspect in YG's Escalade. While they were chasing the suspect, deputies say someone in the SUV opened fire, killing a 65-year-old man on a bike.
YG told TMZ at the time, "I was nowhere near the scene of this incident and had been in a recording studio all day in Hollywood. I was there until after midnight on the Fourth of July and didn't learn of these events until after they happened."
Law enforcement sources tell TMZ ... Sheriff's deputies have made progress in solving the case, but now they need people to come forward. Anyone with info is asked to call 323 890-5500.