Somebody better and faster? Ha not with this truck. Anybody that wants to come to my shop I will turn your truck into gold. A knuter valve is not particularly located on a certain spot on your truck but it is the malfunction of any mechanical device that does not work. And to answer your spark plug question, if you have a truck you should know how to check a spark plug, but for you special people out there here you go, Remove from the cylinder and look at it there if it is black clean it with a wire brush and check the gapping. you can get the info on gapping on the web from the OEM(original eqiptment manufacture) then buy a gapping tool. if the plug looks to have been melted or if there is yellow spots you should take it to the doctor and have its head examined ( buy doctor i mean dealer.) you have got much bigger problems. When installing it make sure you do not overtighten which makes the threads weaker and the combustions eventually blows out.