I recently got a new radiator, for my 1995 Honda Del Sol, about 3 weeks ago and ever since then my car has been acting up. I got to San Diego about twice a week (about and hour drive) and on the freeway my car runs fine...but if I start to drive it around town in stop and go traffic for more than 10 mins. it starts to heat up and overheat! What could be the problem? I have plenty of coolant and I just got an oil change 3 days ago. Please help