I`m having a serious problem guys HELP!! I just went from Rotella 15/40 to 5/40syn. I noticed a slight increase in my idol so I tried to adjust it. What I did was not adjust my idol, but turned the screw on the back right carburator. I didnt realize mistake untill it was to late. It`s my fault cause Ive never messed with the carbs before. I always had the local shop take care of these issue. Now it idols bad and I dont know which way to turn the screw now to fix it. Pls help I`ve been out of work since march of last year so money is soo tight. I installed a home made glass pack exhaust as my mufflers and header pipes were rotten. I getting right around 39.56 mpg on 285mile trip yesterday.When I got back that`s when I noticed the idol problem.