I have noticed that octane changes where you go. WHY? In washington it was all 92 premium. But when i go to cali is 91. Why the change. I can remeber back to my schooling it has to do with the altitude. But that makes no sense now cuase i didn't change alttitude. Why did the octane change. Do i need to change my egde?

 

No need to change any programming unless under 91 octane from my understanding I've never had a problem.