in-line 6 engine...1990 F150 make spout plug

The spout connection is a plug with 2 wires on it that's usually located near the distributor. To set the ignition timing it must be unplugged to disable the electronic ignition timing advance mechanism while you're adjusting the ignition timing. The knock sensor is like a microphone. It listens for knocking or pinging sounds coming from the engine. If the knock sensor hears that it sends a signal to the computer to retard the ignition timing to stop the knocking or pinging. Hope that helps! Jim