Wax got into my ignition cylinder - will it work itself out or do I need to clean it?

You're not doing serious damage by using it, but the gritty feel means there's still solid wax in there catching on the tumblers, so it's worth cleaning properly before your trip rather than hoping it grinds itself clear. I had almost the same thing happen with a house key someone dipped in a jar candle, and a little patience fixed it right up.

The hair dryer idea is actually reasonable. Candle wax softens at fairly low temps, so a few minutes of warm air will make the remaining film gooey enugh to wick out. But don't count on wiping it all with the key itself, that just smears it around. What actually got mine out was a bottle of electrical contact cleaner from the auto parts store. Spray a short burst into the slot, let it sit a few seconds, then work the key in and out gently and let it drip out onto a rag. Repeat until the crud stops coming out on the key blade. It evaporates clean and won't leave anything behind. If the nozzle won't fit the slot, shoot it onto a pipe cleaner or the sewing needle you allready used and feed it in that way. Carb or brake cleaner in a pinch works too, just with more overspray and smell. Skip the WD-40 though. Oil plus leftover wax turns into a paste that catches dirt fast, and that's when an ignition really starts hanging up. Once it's flushed out, the key should turn smoothly and spring back to off on its own. If it still feels gritty after a couple cleaning rounds, the wax has prolly worked down past the wafer springs and it's time for a locksmith to strip the cylinder, wich is cheap and quick on a Corolla. For the weekend, as long as it turns and returns without you babysitting it, you're fine to drive. Toss your spare key in your pocket anyway, because the one thing worse than goo in an ignition is goo in an ignition with no backup.

Funny thing is, way back when, rubbing your key on a candle was actually the old trick for a sticky door lock. Old-timers swore by it. So the wax itself won't eat anything in there, it's just a matter of getting the excess and grit back out. On a stuck padlock once I used a pipe cleaner dipped in rubbing alcohol, worked it in and out a few times, and the wax came off on the fuzz. Alcohol cuts paraffin better than most folks expect. Cheap and no smell like the spray cans. Do that a couple rounds and I'd bet your cylinder settles down before Friday.

One thing I'd add is the key itself. After mine got waxed up by a toddler with a crayon near the front door lock, I kept re-gunking the slot every time I inserted it because I'd only wiped the blade down. What finally broke the cycle was an old toothbrush and a mug of hot water - scrubbed the blade, dried it, and the sticking pretty much stopped after one more flush. Sounds dumb but it's easy to overlook the thing you keep putting back in there. Also check your spare before you grab it for the trip, in case both keys got handled that day.

This might be a dumb question but when you spray the cleaning stuff in the slot, does the wax come out the bottom or does it just stay stuck in there? I always picture the little holes in the ignition as being too tiny for anything to actually drain out of. My kid once got glue on our house key and I just kept wiping the slot with a toothpick until it stopped feeling sticky, took forever. Wondering if I was doing it the slow way the whole time.

Agree with the contact cleaner route, it worked for me after a kid stuffed a crayon stub into my old F150's ignition. One thing I'd add is put an old rag under the slot before you spray, becuase it dripped down my dash and left streaks I was scrubbing at for a week. Also cycle the key in and out a bunch of times between bursts, not just once. Each cycle seemed to pull a little more gunk back out untill the blade finally came out clean.