Do not be reluctant to advice me Iam a mechanic engineer responsible more than 300 trucks and cars most of them working electronic diesel fuel injection system electronic unit injector(EUI),electronic unit pump(EUP) and common rail system , so we need your advice
If I understand you correctly, you desire to add a immobilizer.
Find a 12 volt fuel shut off valve. You can torn it on with a keyed switch , or any other way you choose. The one setup will work on the diesels and gasoline engines if needed.
If you shut off the fuel from a diesel engine, you need to be aware that many of them would need to have the fuel system, right up to the injectors, re-primed with fuel.
It is a good reason with most diesel engines, never to run out of fuel, because of that problem.
Kind Regards....
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