92 dx

i searched but didn't find an answer. this is what i know so far

-only starts overheating while im stopped for a minute or so (when i start moving again the needle drops)
-i've checked the hoses, no kinks or leakage
-upper radiator hose is getting hot
-losing coolant
-overflow is full
-left side of radiator is hot while the right side is cool
-fan kicks on but only intermittently

im thinking its a blockage in the radiator, other thoughts?