Report "2006 hyundai sonata that keeps overheating no sign of blown head gasket . The first time it overheated due to a burned cooling fan connector but it did NOT overheat to the point where steam came out. Had radiator flushed, had thermostat checked, even had cooling fan connected directly to battery and still overheats. I found it doesnt overheat as fast if radiator cap isnt tightened. Car has no radiator leaks, NO milky oil, NO water nor smoke from tailpipe. So head gasket ok? I am completely lost"