I am going to "assume" that you checked the obvious things such as radiator fans are working, and the radiator is in fact not leaking, water pump pumping, etc.
The space under/behind the front bumper is where the cool air comes in and this space acts like a vacuum cleaner and sucks in all kinds of road debris in addition to air.
You need to periodically check the front of the radiator for garbage, etc., obstructing the air flow, and clean it out so that you can in fact get an air flow into and through the radiator for any cooling process to work.
I mounted a screen across the opening to limit the debris from entering the area. My mechanic did it for me from stuff we purchased at Home Depot or other type places like that. We used a kind of chicken wire, and some spray paint to match the color of the car. It has been in place for over 6 years now, with the only incident being last month where my original (1985) lower radiator hose blew out on me. Of course the hose had NOTHING to do with the longevity of non-heat related issues due to the screen allowing for the radiator to breath.
|UPDATED|9/28/2014 3:16:28 PM (AZT)|/UPDATED|
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