Шершень прав.. лучше гуглить не ленитесь..
Хрень эта типа бустера напряжения для топливного насоса.. поднимает напр. питания на нём до 16,5В. на короткое время (очевидно при кикдауне), шоб ФСОшники в отрыв как боинг уходили
http://www.fullsizechevy.com/forum/archive/index.php/t-145855.html....The "final" end of the saga: Mercury Magnetics, among other things, supplies Whipple Superchargers with Power Transformers to be used as fuel pump boosters -- that is, they supply increased power (16.5VDC) to the fuel pump under "increased fuel demand" for a short amount of time (so as not to burn out the fuel pump). This is the unit that burned out, thus the loss of power to the fuel pump.
Hopefully someone else will read this and REMEMBER it before they go replacing a perfectly good $200 fuel pump and wasting a perfectly good afternoon doing it! Trace that wire! Find that short!