88redyota4x4

Hey guys just like the title sais,problem just started yesterday on my lunch break. When I got home from work I pulled the plugs and there a reddish brown color with no build up, plugs are the go to factory ngk btw. Tried to adjust the idle but didnt have any affect. Swapped in a msd coil I had laying around and it didnt help either, and as far as I can tell theres no vaccum leaks. And the tank is about half full, this batch of gas has been in for about five days, and the problem just started yesterday at lunch but it was fine that morning, so I dont think its water in the fuel, any ideas are appreciated thank you