[Badbubba]

You don't need a ground or power for the solenoid to seal shut. You have a bad seal in the solenoid or a score or a nick. Make sure you don't have power on it either. Btw. Ideally your gauge should measure bottle pressure, need to empty to install. Or put gauge on the line side which will only measure pressure with the bottle open. Unless you used a torch to heat the bottle or have a malfunctioning bottle heater/pressure switch, you shouldn't have excessive pressure. You should also have a rupture disk too. You need correct bottle pressure to achieve the proper shot. Just bc you have 100 shot jet, doesn't mean you will get 100 shot worth of nitrous, depends on correct bottle pressure. Was the car running when you opened the bottle, if not, you need to be careful so that you don't fill your intake with nitrous and then try to start it.