[Wbulk]

Back to the origninal question about the diode. The diode goes on the wire that connects to the I terminal before your volatge regulator. If you have a charging light it goes between the light and the I terminal. This prevents current flowing backwards from the alternator to your ignition system after the ignition is shut off. This in combination with to high an idle and or to advanced of timing contributes to run on or dieseling. Like has been said, the solenoid works good, but I have seen some cars with a solenoid continue to run without the diode. This can be caused by hot desposits in the combustion chamber and with possibly the regular idle screw not backed out far enough. A leaky power value also can contribute to the problem. I believe you can buy the diode from Haywire.