Why does the exhaust pipe discharge water in winter?

1 Answers
JourneyLee
07/30/25 10:54am
In winter, water discharge from the exhaust pipe occurs because the three-way catalytic converter releases water vapor during operation. As the temperature of the exhaust pipe decreases, this vapor condenses into water droplets that flow out with the exhaust gases from the tailpipe. Below are specific details about the automotive three-way catalytic converter: 1. Water discharge phenomenon: When the car is idling or running at high speed, water droplets or streams often drip from the exhaust outlet at the rear of the exhaust pipe or from the drainage holes beneath the muffler. This indicates good engine combustion conditions and normal operation of the car's three-way catalytic converter. 2. Working principle: The working principle involves the chemical reactions within the three-way catalytic converter, which transform harmful gases such as carbon monoxide in the exhaust into carbon dioxide and water.
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