You haven't mentioned how many miles are on your car.
But I did! 
It’s got 49k miles.
How's your gas mileage been? Notice any meaningful reduction from what you'd been getting before this problem began?
Not really sure, haven’t been paying close attention to that. (Work, family, other obligations---DISTRACTIONS! They're everywhere!) The OBC read-out is now at 19.6, but it’s been a l o n g time since I reset that. I do a fair amount of stop and go driving, with some highway time sprinkled in here and there, so I suppose that’s not too bad for a 3.2 (Right?). There hasn’t been a noticeable drop, as far as I can tell. I went ahead and reset the MPG just now.
Have you considered the oxygen sensors? One or more may be iffy, but not bad enough to flash a CEL at all or may only do so intermittently. When my brother owned my '02 S it flashed a CEL at 64k miles and the mechanic replaced one faulty O2 sensor; all was good. I bought the car at 68k miles and read on this forum that it's best to change all 4 sensors at once, so I replaced the other 3 myself and the idle, while not bad before, was very noticeably smoother, and mileage improved 1-2mpg, as did overall driveability.
Nope, hadn’t considered them…that’s why I have you guys! (I’m relatively new at this DIY car stuff.) Point taken, thanks.
Hooking up a code reader of some kind (I picked up a 2nd hand Durametric but haven't had to use it yet) could yield lots of good troubleshooting info. AutoZone will let you borrow a basic one for free.
Yeah, I thought about stopping at AZ on the way home but really didn’t have the chance (needed to pick the kid up at school). But the first time this happened (the several hundred miles ago time) the AZ code reader came up “no code”, presumably because the CEL was no longer on (which is the situation right now, as well). My regular mechanic’s equipment, while not the ‘official’ Porsche one, was more sophisticated---it gave me the misfire info. I’ll try to stop by there again and have it rechecked.
Based on all the things I've read on this forum I'd also look into cleaning the throttle body. My car's probably due for that now too.
That seems to be a recurring theme; I should probably do that. At 49k miles, I suppose it wouldn’t be unusual for that to need to be done, Right? (I have no idea if it was done before, but I got the car at 19k miles, and I know I haven’t done it yet.)
Your CEL misfire on cylinder #1 could also mean a faulty plug or a faulty coil pack on cylinder #1.
How many miles on either? Perhaps it’s time to replace plugs & check the coils for cracks and ingress of moisture.....
As with the TB cleaning, gotta plead ignorance on this one, too. I only know I haven’t done anything with the plugs/coils. (I don’t suppose these are things that they would have done at the 30k maintenance---at a Porsche dealership---are they? ‘Course, that has been 19k miles ago anyway.)
I tend to agree with Steve.
If it is an oxygen sensor you will more often than not experience misfires in an entire bank of cylinders and a further code for the sensor.
Check the code again, if it is the same code for cylinder 1 then pull out the coil pack and check it.
It is a good place to start at any rate.
All good stuff. Thanks. I’ll get the code read-out first and see where that takes me… BTW, if it does turn out to be cylinder 1, anyone know if that's one of the 'hard' ones or 'easy' ones to get to?