Check to make sure the solenoids click. You can do this by shutting off the bottle, and clearing the lines of N20. Then turn the car to the on position, arm the nitrous switch, and step on the gas. You should hear them click when you reach WOT. If they work, your bottle pressure was probably too low. Optimum pressure is 900-1050 psi, anything under 900 you won't really feel much. I hope you have a pressure gauge. You should feel a 75 shot.