I've been using non-abrasive Goop hand cleaner. Dab some on the sap, let it sit, it softens it up - fingernail if needed - wipe off. Figure it's also taking my wax off the hood, so after sap removal, I re-wax the hood. On dry, old sap that has hardened, if you're really careful, you can use a razor blade style scraper. ST