I will disagree on your octane statements based on a few vehicles in my 44 years that I have owned and a 2004 Volvo s60 turbo my wife drives and how the lesser gas makes it pings and gets terrible mpg while the 93 runs smooth enough to pull 30mpg. And if you ever owned a ford that has labor knocking on 87 octane,you will know what I mean about better gas.lol

I was leaning on the pcv and the fuel filters.I want to say the previous owner did a lot of the other things on the truck. But a once over should get it all straightened out.thanks