The problem might not be the shutoff valve. Connect your MityVac directly to the vacuum line to the shutoff valve and see if it stops the engine. If so, then your problem is elsewhere. Most likely it is something in the door locks or the climate control The MityVac will help you track it down.

__________________
Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
Chain Elongation References