Could def be AOS, as that can also cause the P0456 error code I was getting intermittently over the past few months. It's smoked occasionally on startup from cold but nothing like this, this was next level. Thankfully I wasn't far from home.
I haven't opened it up to check hose fittings. The last time I had 0456 code one of the hoses was loose so easy enough. But all the misfire codes (for all cylinders) leads me to believe it's not the charcoal canister anymore...but what do I know...
The spark plugs are pretty new (2 years old max) so I'd hope it's not that. AOS seems like a likely culprit, but to your point I don't want to run the engine if I don't have to; probably just have it towed to my indie
2004 Boxster S. Mileage is 74K