No, it was the one under the steering column.

 

The main relay is not located in or around the under-dash fuse box. It's on the right side of the glove box.

 

Good, that makes me feel better about things just being coincidence. I wonder why it took so long to start up though.

I was thinking about how I have a new exhaust. How much will they normally smoke before they don't smoke anymore?

 

Maybe fuse 13 or 31 for the main relay or fuse 9 for the distributor was loose and your hammering caused one of them to make better electrical contact.

For now, just keep your eye on the white exhaust smoke (as well as possible engine over-heating and coolant loss) and hope it goes away.

 

I got a look at the smoke during daylight and it isn't nearly as thick as it seems at night. One probably wouldn't notice it unless observing closely.

Here's a short video of the idle problem...

http://www.youtube.com/watch?v=IkcLL_LsP1I

 

Yeah, I couldn't see any white smoke in the exhaust.