Can't seem to be able to fake out the pcm that the valve for the cannister is still hooked up. With ignition on, the pcm sends 12 volts and checks the circuit before the engine is even started. I've grounded the negitive side and the pcm still knows it's not plugged in. FI code is that the system is grounded(with the valve just unplugged). Cannot find a schematic on this in the service manuel.