#1 spark plug melted? Options

[Justin]

I have sprayed my celica with a 75 shot for 3 10lb bottles and then I stopped. That was around 2 or 3 weeks ago. The engine ran perfect and did not lean out. I have a full exhaust and cai. Then a couple of days ago I heard an exhaust leak around the stock header. So, I took it off to check the gaskets. When I was taking it off a bolt crossthreaded and broke in one of the flanges. It broke at the end of that 1st cat on the header, right before the flex pipe. So, not having any tools to remove it I had to drive it that way for a few days. So Monday I put a little pipe to connect the two sections, it leaked alot but worked. Now today when I pulled off the #1 spark plug wire I halfway broke it because it seemed to have melted a little on the inside. Then I look at the spark plug down the hole with a flashlight and the sides where the socket grabs onto almost look gone lik ethey melted. It still runs good except it did misfire a couple of times in 4th gear at like 2.5k but then didn't do it anymore.

Anyone have any ideas on what happened or what is wrong.

[shadycrew31]

nitrous, stock engine, 75 shot nuf said....

[Justin]

So, is it going to go downhill from here. I mean it only started missing after the whole header incident