I have a 99 Honda Accord with 190,000 miles on it. Occasionally when I'm driving down the road (highway and residential) the engine cuts out, as does the power steering, rpm gauge, and speed gauge. The radio and the lights stay on though. This had happened a few times in the past, but it's happened a few times in the last month. Before I would pull over, turn it back on and keep going, but on an hour long car drive I pulled over, restarted, then stalled out again at ~60 mph, about 4 more times, then I got off the highway and was fine for the rest of the journey.
I know that Honda had a recall on the ignition keys, and mine was replaced, but from what I understand that doesn't fix the problem sometimes and needs to be replaced again. I haven't noticed if the green key light on the dash stays on or not (I didn't know I needed to be looking) and I can't figure out how to recreate it, as it seems random and I have tried jiggling with the key while driving. Any useful advice or insight?

 

Since the ignition switch provides power to the ignition and to the radio, assuming your radio isn't always hot, it's unlikely the ignition switch is the culprit.

I would hook up a fuel pressure tester from Harbor Freight and lay the hood down on it so the gauge faces you inside the car. Drive around, if the car dies and fuel pressure drops off at the same time it's likely the main relay is the culprit. If fuel pressure stays high, then it's likely the issue is spark related.

Possible culprits are the ignition control module or the ignition coil.