Windshield fogs up fast in dry weather: heater core leak vs cabin moisture sources
If your windshield fogs up quickly even when it’s dry outside, the problem is usually moisture trapped inside the cabin—or, less commonly, coolant vapor from a leaking heater core. Use the symptom checks and step-by-step
AC blows cold then warm at idle: low refrigerant vs weak condenser airflow
If your car’s A/C is cold while driving but turns warm when you sit at a stoplight, the problem is usually either (1) not enough airflow through the condenser at low speed or (2) a low refrigerant charge from a leak. Use