well on a serious note , I was just checking my car's battery yesterday and car's engine was just started ,That engine temp thing was just I was checking too,Usually people follow The 'C' Sign on the honda city lol ,So Me do that too ,so yesterday me ne kaha kiu na check kia jaye kia scene hai I was checking the engine temp when the 'C' Sign went off ,Trust me man the engine was as cold as it could've been ,Leave the car on idle start at least couple minutes after the 'C' Sign goes off .and I learnt that yesterday lol