Sabreflier

Does anyone have recommendation for a Time-off relay to use with my NEX? On a diesel you need to turn to accessory power to warm-up the glow plugs. The NEX starts to Boot. Then after 10-15 sec when I go to start the truck the NEX momentarily loses power and reboots again. I need to figure out how to maintain power to the NEX so it only goes through one boot. Anyone solved this already?