Here's why:
* Combustion Process: The engine burns fuel and air, producing exhaust gases that contain water vapor (H₂O) as a byproduct. This is because hydrogen in the fuel combines with oxygen in the air.
* Cooling: The exhaust system is hot, but as it cools down, particularly when the engine is first started or after being run for a while and then shut off, the water vapor condenses into liquid water.
* Tailpipe as the Coldest Point: The tailpipe is often one of the coldest points in the exhaust system, especially after the engine has cooled down. This makes it the place where the most condensation occurs.
When it might *not* be normal:
* Excessive Amount: While some dripping is normal, an unusually large amount of water could indicate a problem like a coolant leak into the combustion chamber (a serious issue requiring immediate attention). This would often be accompanied by other symptoms like overheating, white smoke from the exhaust, or sweet-smelling exhaust.
* Other Fluids: If the liquid is colored (milky, oily, etc.) or smells unusual (like antifreeze or fuel), it's definitely not just condensation and points to a leak of some other fluid into the exhaust system.
In short: A little water dripping from the tailpipe of a 2003 Chevy Blazer is usually nothing to worry about. However, if the amount is excessive or the liquid is anything other than clear water, have a mechanic inspect it.
