Johnny Wactor Murder, One Suspect Pleads Guilty to Attempted Robbery, Grand Theft

One of 4 suspects charged in the Johnny Wactor murder case has pled guilty to attempted robbery and grand theft charges.

Leonel Gutierrez , 18, is free on bond while he awaits sentencing in November ... and faces up to 5 years in prison.

The "General Hospital" actor was shot and killed back in May after leaving his job as a bartender in downtown L.A. Prosecutors say he was shot by one of the suspects, Robert Barceleau , in the chest after confronting a group of men allegedly trying to steal the catalytic converter from his car.

Two of the 4 men -- 18-year-olds Barceleau and Sergio Estrada -- arrested in Johnny's slaying have been slapped with murder charges.

The fourth suspect, 22-year-old Frank Olano , faces charges of accessory after the fact to murder, receiving stolen property, and 3 counts of being a felon with a firearm.

They’ve pled not guilty and are set to appear in court next month.