When to change hot plugs?

Hot plugs, or spark plugs, should be changed based on the manufacturer's recommended maintenance schedule, typically every 30,000 to 100,000 miles, depending on the type of plug used. Signs that they need replacement include poor engine performance, difficulty starting, reduced fuel efficiency, or engine misfires. Regularly checking the condition of the plugs during routine maintenance can help identify when they need to be replaced. Always refer to the vehicle's owner manual for specific guidelines.