To begin, I'm about 99% sure nothing like this exists, maybe legal/liability reasons, or just not enough demand.
So, as most of us are aware, when you initiate a remote start cycle, the vehicle will of course start, then enter a state where all the doors are locked, the engine is running without a key in the ignition, if the hood is popped it will shut off, unless extended it will shut off after 10 mins, and the vehicle can't be shifted out of park (or maybe if it is, it shuts off...not certain on that one).
Ok, all that said, I frequently have situations where I would like to exit the vehicle, leave it running, but have it secured. Maybe I want to run into a convenience store real quick to grab a drink, or I live in an apt complex so I stop at the mail box station and want to get out to check my mail. I hate having to shut the vehicle off in such situations only to be restarting it again 2-5 mins later.
It's a shame there isn't a way once the vehicle is already running with the key in the ignition that you can't put the vehicle into that same "remote start mode", where you could then turn the ignition off and remove the key, open the door, lock the doors, close the door, and then have the vehicle left in that same engine running remote start state for the next 10 mins where if tampered with it will automatically shut off.
I suppose if I wanted the ability bad enough, in theory a "turbo timer" device would accomplish the goal. For any of you unfamiliar, some people are of the opinion that the life of a turbo is cut short if it stops spinning when it is still hot, so a turbo timer is a device that will keep a turbo charged vehicle running for a preset amount of time after the ignition is switched off to ensure an adequate cool down period.
And now I return you to your regularly scheduled forum browsing.