Running rough

[Tony91]

Recent new member. hoping to get some answers. I have a 91, its been runnig fine I took it out this morning and on the way back home I heard a noise ( not a knocking sound more like a ticking popping sound) now its running rough. I was able to limp home pulled in the garage and reved it up it feels like it is missing. I just fueled up with 100 octane would that have anything to do with it? any suggestions? Thx