I'll follow this thread, would be a nice to have. An additional relay to the glow plugs wouldn't be hard, but with the key physically in the off position the vacuum is engaging the fuel shutoff valve.

Seems like an electric vacuum switch would be in order as well to bypass that, but have it reset after a period of time. Not a bad plan really, have it reset after 10 minutes, that way if there's an accidental start from a rogue signal the car will shut itself down in 10 mins ....or maybe 15 if you like longer warmups.

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