I was just putzing around under the hood a couple days ago, and I decided to do some degreasing, starting with the mount for the ignition coil, which had a layer of black gunk about 1/4". I proceeded, mostly out of boredom, to disconnect the wires, clean up the terminals, and sprayed electronics cleaner all over and in.

I put it back, then found a vacuum hose to the throttle body that was disconnected. I reconnected it.

Just for giggles, I started the car, took it around the block, and came back home. I turned it off, then on again. It sounded good. I later took it down a couple miles to the parts store, left it running, just in case, then drove it home, making sure I got it all warmed up. It cranked up again, nice and healthy sounding.

Did reconnecting the vacuum and cleaning the ignition coil really fix this?

I've been driving it for several days now, and I havn't had one problem.