At mid to heavy throttle (probably because of engine noise), I don't notice it, but there is a light tick... . tick..... tick... . tick sound that eminates from the driver's side of my truck that sounds like an exhaust leak. OK, we know it's not that... ... but... ... what is it? It only does it when idling with my foot resting on the accelerator pedal..... not pressing it... . just taking the "slop" off of it, OR when slowing from "Ramming" speed with the same rest on the pedal! I know one of you (or maybe more) know what this sound is... ... it drives me crazy because I don't know WHAT it is? HELP!!