If you wash your motor with water, then water could've seeped in there.
If you know that there is spark at the distributor cap then I would think it would be bad spark plug leads.
A drain plug for a spark plug? Now why would there be? What would you drain from a spark plug.... the spark? If you're referring to a plug for the spark plug socket, I'm sure you could find something that would fit that would keep out debris while you let you engine sit without plugs. (Why??)
bad spark plug wire.
There mgith be no spark because there are different reasons.one is there is rust on the flywheel. Second is that the coil is to far away.
Start by checking your spark if you don't have spark check the spark plug. If the spark plug is ok then check your flywheel - It may have rust on it. Clean it up and clean up your coil and see if you have spark. If you still don't have spark change your coil. If it has spark and no fuel - clean your carb.
The spark plug gap for a 2003 Buick LeSabre should be set at .060 inches. The best spark plug for this vehicle would be an Iridium plug.
Bad spark plug, bad spark plug wire
Just a wild guess, but I would start at the top of the heads.......should see a spark plug wire connected to a plug........viola! spark plug.
You just have to grab with a pliers and pull it out. You will have to twist and wiggle to break the rust though.
You would likely need to pry it up as you turn it. The problem will be getting a new spark plug in, since you likely damaged the head. Once the spark plug is removed, you would likely have to sleeve the hole to get a new plug to stay.
If you mean that the wire came out of the boot, then pull the boot off of the spark plug and use a spark plug socket to remove the spark plug.
damaged thread in head or spark plug. not tightened right or damaged plug