This mission doesn’t appear as an official side-op and won’t register as one on your map. It’s in the same neighbourhood as the Ripcode side op – South Oakland. Use Nethack in the area to find it.
Hack the ctOS box to get a view into the garage where Emilio is trying to gas himself. Hack the car to sound the horn and attract some attention. You can try to hack the garage door or the extractor fan, but they’re both broken. The horn will attract someone’s attention and they’ll eventually save him.