Your probably not hooking the relay up right. There are numbers on the bottom of the relay next to the connections. #30 on relay goes straight to battery. #84 goes to ground. #85 goes to whatever you are using for a switch whether it be the ignition switch, toggle etc. This is your relay activation voltage.#86 and 86A are for the pump positive wire. Put it on #86 to come on when you activate your switch. If you put it on #86A, it will come on as soon as you connect it, and go off when you activate your switch. Connect the grond to the pump to the frame or engine ground.