Mazda MPV rear heating line rusted and leaking coolant, causing starting issues and requiring replacement on Mazda MPV

Some Mazda MPV owners report experiencing coolant leaks due to rusted rear heating lines, which can lead to unexpected coolant loss and potentially leave the vehicle stranded. This issue is particularly prevalent in models like the 2002 Mazda MPV that feature rear heating and AC controls in the right rear passenger compartment. Owners are advised to take prompt action to address these leaks, as running the vehicle with insufficient coolant can cause engine damage. Repairs may involve replacing the rear heater pipes, which can be costly, averaging around $1000 for parts and labor. To prevent such leaks, it is important for owners to be aware of common causes, such as hose and water pump failures. Additionally, Mazda has made changes in production, including switching the heater pipe material from steel to aluminum and adding a urethane protector to mitigate these issues. Regular maintenance and vigilance regarding coolant leaks can help prevent serious complications in the future.