I can beat this for solutions. All you need to do is splice a switch into the ground lead to the fuel pump. Then hide the switch completely out of sight.

There will be just enough residual fuel pressure to start the car and get into the road or middle of the parking lot before the car runs out of fuel. Alarms are universally ignored and no more that owner/neighbor nuisance devices. However, a car broken down in the middle of a right of way gets everyone’s attention. The thief will abandon their effort immediately every time. You can place the switch anywhere, so the lack of standardization and obscurity means no one will be able to defeat this unless they know you and the modifications you’ve made.

If you want to get even more integrated, use a microcontroller either placed on the vehicles CAN bus or simply wired to the relevant circuits. Use the microcontroller with a relay to connect the fuel pump only if the vehicle is started with a certain circuit or series of circuits activated. Like, the right blinker must be on when the key is turned (button pressed) in order for the relay to close.

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