Chrome and steel (all metals) conduct electricity to one degree or another (there is a table in my Engineering manuals that lists the conductivity of metals (Silver, Copper, Gold, Aluminum, Zinc, Nickel, Brass, Bronze, Iron, Platinum, Steel, Lead, Stainless Steel, etc. for every known alloy, or elemental particle). Your plastic covered water pump is a different story. Plastic is an insulator (why your wires are covered in colored PVC plastic).
You can grind it off, or relocate the cable to a different grounding point like the intake manifold.