Im more concerned if the wire might have any breaks or chaffing inside the harness or hidden, and my opinion is extra grounding could never hurt, which is why I want to splice a new ground along with the old ground. I just dont want to have to deal with chasing down issues that are a bad ground that is hard to trace is all. I just was worried about adding another ground might short something or cause some issues maybe with another sensor but Im not sure how. Mostly worried about ecm issues. The knock sensor wire I want to replace because the heatshield for it by the trans is pinned between the hot trans bellhousing and the passenger exhaust manifold, with the wire touching the manifold side of the heatshield touching the manifold, so I figured i might as well run a new wire just in case that wire is shorting sometimes or melted in some way, causing timing to retard like how it is. Mostly I just want to rule out every possible cause before I throw an ESC at it for like $150.IDK, it may work, it may not. The Knock Sensor works on resistance so, if you loose, or change it, you may have issues. There's a reason GM did things, mostly expense but it could be "cross talk" between different sensors/components. What I was asking, did you check the ground wire from the ESC to its grounding point? If it's still good, why f**k with it? If you do, try to get it as close to OE as possible.