We were driving for about 4 hours in West Texas heat, towing a trailer and we had suddenly started getting hot air and then going back to cold. Then hot air, then Cold. We went over a bump and suddenly our car smelled like nail varnish. We thought it was the town so we stopped circulating air in the car and the smell stopped but it came back again within 5 mins or so. Then we turned it off completely but could still smell it. It came back and stopped multiple times during our driving and then stopped for a long time, but then we stopped for a while and I could smell it in the passenger seat so strongly I had to open the car door. The passenger floorboard was hot and my husband said he thought that could be a symptom of a catylytic converter? We have no idea what's happening.
My car has 125638 miles.
My car has an automatic transmission.
The catalytic converter may be getting overheated and turning cherry red, causing the hot floor and burning smell. The engine may be running too rich which can cause this problem as well. Also, towing the trailer can overheat the transmission. It can reach a point where it will start to overheat the engine. Do you know if the trailer exceeds the towing capacity of the vehicle or not?
Another possible problem you stated was the A/C going hot and cold. This means the A/C is not working correctly as well. Check to make sure that the A/C blows cold after the engine cools off. If it does not blow cold any more then you may have blown the A/C evaporator. This would explain the nail polish smell. It could also leak refrigerant and oil out of A/C drain. The fluid can get on the exhaust and can also cause a burning smell. If you need help fixing the issue, consider YourMechanic, as mobile mechanic to come and check it out. They will be able to perform checks on the components I've mentioned and diagnose the smell you're experiencing and your A/C issue firsthand. Good luck.
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