2001 Accent 1.6L

Previously my car had a problem running in the rain and the best solution received was to replace the spark plugs and spark plug wires. I have replaced the wires but not the plugs as yet.

I did notice that when I replaced the spark plug wires, one of them, on the end that doesn't connect to a spark plug, was corroded. And inside the plug itself is still corroded.

I'm wondering how I might clean that out without electrocuting myself?

Car is still running badly and the CEL is either on steady or flashing madly. Not that it needs to; I can hear and feel the engine misfiring or hiccuping or otherwise just not running properly. So I'm hoping that changing the spark plugs (again - they're less than a year old!) and cleaning out this connection for the spark plug wire will solve the problem.