if car is stumbling with test you have alky
is this a recent kit , older kits (pre 2005 i think) dont change red to green as they didnt have the presssure sensing or dual color led
if led doesnt turn green you could have a ground issue with the wire (the one with the loop terminal) at the pump head that signals the green light, find a better ground point
i usually extend that wire to the pass fender since thats where all the battery grounds are
aside from that check that the pac green wire sees 1.6v at key on, if its not connected and seeing 0v holding the test still may not turn the led green and you also wont have alky turnon under boost