The radiator cap is a pressure release valve designed to build cooling system pressure at extreme heat. Normally designed to hold between 8 and 15 PSI, it's important that
have the capacity to maintain sufficient pressure. An under-pressurised system may result in the car overheating.
So that the system doesn't become too pressurised, at maximum PSI the radiator cap valve opens and coolant escapes through the overflow tube into the bottom of the overflow tank. If you are experiencing temperature fluctuations, maybe your engine is overheating or you notice steam coming from your radiator, it may be time to replace the radiator cap.
for any car are readily here at Euro Car Parts.Show Less... View More