I have had issues at the negative post on the battery. I had replaced the terminals and lost some length on the cables. Everything looked ok, but there wasn't a lot of slack on the ground cable. The biggest issue was with the part that clamps onto the cable and bolts to the intake. I guess that whenever the engine would turn over, or the transmission would shift, it was always tugging on the cable. I was having some strange symptoms, so I examined the battery cables. Whenever I touched the ground cable, it just fell out of the terminal. I bought some wire lugs and used a peice of cable to extend the ground point from the intake. The improvement in performance was better than any tune up I had previously performed. Hope this helps.