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Trying to find out why engine stalls out after letting off of crank positon. Fuel being cut off.

Backprobed to fuel pump relay is cutting power to the fuel pump. Checked relay - OK. Found black/red wire cutting power from circuit opening relay. Backprobed from circuit opening relay via the green wire and found power is being cut from there. Tested at ECU pin- same thing (power keeps cutting out after crank is let off). Asked local Toyota dealer tech as to what sensor/switch/factor engaged the fuel cut-off when in an accident; they were unable to answer. Attempted to check online at several sources, but to no avail.

Does anyone know how the fuel is cut out when this car is crashed? I know there is a fuel cut-off of the manifold pressure exceeds 14-5psi (due to the turbocharger) to protect the engine itself.

Any help would be appreciated!

Do not think this has a fuel cut off on it. Sounds to me like the ignition switch is bad.

Something has to cut the fuel off in the event of an accident. The computer sends power to the circuit opening relay which sends power to fuel pump relay, which sends power to fuel pump. Tested the ignition switch- its good.

The vehicle must be in the crank mode to get any fuel pressure. The circuit opening relay is only energized during crank or when the airflow meter door is open, then sending voltage to the Blue/Black trace wire at the fuel pump relay. Have you checked powers and grounds at the computer?

Sorry, been out sick lately, and we're back on it this weekend. Yeah- checked powers and grounds at computer and they are good. There is a green wire coming from the computer and going to the fuel pump relay that (by design) is supposed to take over the power supply to energize the relay (and in turn the fuel pump), but the computer cuts that power out when the ignition switch springs back from the CRANK to the ON position. If we do hold the ignition switch in the CRANK position, it will stay running. If we manually jump the black/red wire at the fuel pump relay from the positive from the battery, it will stay running so at least we can move it in and out of the shop.

if all fuses are good and i believe there are two or three ignition fuses i would get an ignition switch and just plug it in and see what happens. i've over complicated issues before when the answer was simple.