!st off you should check for 12v at the stop solenoid by turning key switch off and on. If you do hold on to the solenoid you should fell the plunger moving inside the solenoid. If its working then it has to be in the stop valve itself. If it isn't then check for a good ground, then check the wire all the way back to the key switch. Make sure the switch has 12v to it and if not check the red wire to fuse and from there to battery. You should by now found something and if you did what was it.