my del sol just started overheating on the highway.....the strange part is, it only does it if im cruising at the same speed for 30 mins or more, if i turn my heat on it cools down. it does NOT overheat OFF the highway even if i get on it hard.....the only thing i can think of it that there is a large area of fins missing on my radiator.....any ideas?

 

new raddiator?, check make sure fan is working.

 

yea i think and hope its the radiator.....i know the fan is working