Ask you service station manager if they change the gasoline mix in your area seasonally. Oct is when they switch to winter gasoline here in CA. That might be a clue to your problem. If it is, there isn’t much you can do about it other than switch to the higher octane in the winter. You are right to check the EGR and the knock sensor in any event. Those are usually fairly easy to check.
A basic tune-up, new air filter, engine timing, then valve timing would be the next on the list probably if the prior doesn’t fix it.
“how would I know if have a fault code?”
Your CEL would come on…It’s not the gasoline…
With that kind of mileage, carbon deposits (actually ash from burned motor oil) can build up and raise the compression enough to cause this…There are chemical products that claim they can remove these deposits. BG Formula 44K is one of them…Add that product to the tank when it’s down to 1/8 full and take it out and do several full-throttle accelerations maintaining full throttle for as long as it’s safe to do so. In other words, take it out and blow the cobs out of it…