The gas changes every week or less so once the salt is washed away this tank will go quick. The code is P0300 and its a stored or permanent code now, it just reset itself during warmup session. I fill the tank just before the first snow so I can run & jog it, till spring. So the present gas is three months old.
It has to go to the dealer for a Takata airbag recall. One of the guys there is pretty sharp, so I will have him vacuum the ECU and zero it out. The track opens in mid-April, so it will have fresh plugs, gas, oil, and air filter.
I'll have to go a back road to collect some freeze frame data.
As I said 93 goes off pretty quick it could have gone off in 3 months.
In a Hellcat this could easily account for the feeling the engine lost "200hp".
91 gasoline went stale in around 6 months in my sister's Infiniti. Engine started and idled ok. Car ran ok but the engine felt flat.
Being unfamiliar with the vehicle I just assumed it was a dog. But after the fuel tank got low and I refiled it with fresh Shell V-Power 91 which is what she used the engine was transformed. It was not a dog at all. The gasoline had just gone stale.
The P0300 is random multiple misfire fault codes. That a sign of a systematic problem. I'm liking "bad" gasoline more and more.
While the P0300 is now "permanent", after so many warm up cycles provided no more misfires the engine controller will then erase the code. In the meantime you should be able to clear it from active status and extinguish the CEL. However, if the light comes back with that code as the reason then the engine controller is detecting random multiple misfires.
If you continue to drive the car I would not push the engine hard until you have run the fuel tank level down to say around 1/4 tank and then had a chance to refill it with fresh 93 octane gasoline.
I'd replace the plugs with new factory recommended plugs unless you have a "tune" and the manufacturer of this has another plug recommendation.