Car Overheats in Traffic

Sitting in Jacksonville traffic watching the temperature gauge climb is nerve-racking. If it only overheats when you're barely moving, the fix is usually targeted.

Overheating exclusively in slow traffic or stop-and-go conditions is a ventilation problem. At speed, wind pushes through the radiator and carries heat away. In traffic, that job falls to the electric cooling fan — and if it's not working, heat stacks up fast. A dead fan motor, blown fuse, failed relay, or bad coolant temperature sensor that never triggers the fan are all common causes. In Jacksonville, where traffic crawls on I-95, JTB, and 295 every rush hour, a weak cooling system gets exposed quickly.

Beyond the fan, a partially clogged radiator shows its weakness in traffic too. At highway speed, forced airflow compensates for reduced radiator efficiency. In traffic, there's not enough airflow to make up the difference. Old coolant that hasn't been flushed allows corrosion and scale to accumulate inside the radiator tubes, blocking flow. A system that's "fine" in January might overheat daily in July when ambient temperatures add to the load. Also check that nothing is blocking the radiator from the front — plastic bags, cardboard from a previous winter fix, or a damaged condenser can all restrict airflow.

Don't sit in traffic white-knuckling the temperature gauge. Call our mobile mechanic team at (904) 788-7272 and let us come to your Jacksonville home or office to diagnose and fix the cooling system. Fans, relays, coolant flushes, and radiator replacements — we handle it all on-site so you can drive through rush hour in peace.