My '90 8.2 t quit one day; shut her off to fuel, didn't start back up. After cranking and cranking w/ether, noticed what appeared to be a motor smoking. An hour of cool down and she fired right up. The "motor" is actually a "work solenoid", made by Trombetta. It has slways started since then, but figured it should be replaced, since it was smoking. Lookng for a replacement, the DD dealer asked "do you mean the shut-off solenoid?"
"I guess so; what happens when it goes bad?"
"It wont start"
Front center of engine, boxy unit where the throttle cable is attached, on drivers side. Sticking out horizontally w/a 2 wire connector. looks like a small DC motor. Only thing there w/wires attached.
I don't know how to check it, but something to keep in mind.