It’s probably not your fault. It always annoyed me when old (20-30 years ago) Shell gas commercials would imply that high-octane (read: much higher profit margin) gasoline would cause your engine to make more power. Now, they didn’t actually say that outright, because it’s not true.[0] But if you put Shell gasoline in your car, you were told that you’d “feel the power your car is capable of”, or some weasely bullshit. The word “power” was used a lot in that commercial, just never next to the word “more”.

I was a professional mechanic around that time, and I had coworkers that thought that not only would high-octane gas give more power, would also swear it increased fuel mileage. Neither is true. High-octane fuel has less energy per gallon than lower octane fuel, it can’t give better mileage. (Now, “mechanic” != “engineer”, but c’mon, guys.)

[0] Yes, Captain Pedantic, I’m aware of knock sensors and computerized ignition timing. It was a quarter century ago.