i use wd40 on the really bad spots an wipe them down, then i spray woth gunk foaming engine degreaser, let it soak for about 2 min, then lightly aggitate bad spots and hose down. just wipe it down with towel, turn engine on an then i spray everything with megs foaming tire spray an close the hood. let it glaze over for 30 min or whateva an wipe excess off. dont forget to cover distributer an wires. but those products i mentioned worked great on an 8 yr old untouched engine