Symptoms / Coolant leak (puddle or dropping coolant level)
Coolant leak (puddle or dropping coolant level)
Address promptlyA green, orange, or pink puddle and a sweet smell mean coolant is escaping — a leak that can lead to overheating.
What this usually means
Coolant (antifreeze) circulates through the engine to carry heat to the radiator. A leak — visible as a bright green, orange, or pink puddle, a sweet smell, or a coolant tank that keeps dropping — means the system is losing the fluid it needs to stay cool. Left alone, the level falls until the engine overheats. Finding the source early, while it’s a hose or clamp rather than something internal, keeps it an inexpensive fix.
Most likely causes
- highCracked or loose hoseRubber hoses harden and crack with age; a loose clamp leaks at the connection. A common, cheap fix.
- highFailing radiator or radiator capA corroded radiator or a cap that no longer holds pressure lets coolant escape.
- mediumLeaking water pumpA worn pump seal weeps coolant, often leaving a trail near the front of the engine.
- mediumFailing thermostat housing or gasketPlastic housings and gaskets crack with heat cycles and seep coolant.
- lowHead gasket leakAn internal leak can burn coolant in the cylinders — serious, sometimes shown by white exhaust smoke.
Is it safe to drive?
Typical fix & cost
Most external leaks are a hose, clamp, cap, or radiator — moderate repairs. A water pump is more involved. An internal (head gasket) leak is the expensive exception. Pressure-testing the system pinpoints the source so you fix the actual leak.
Typical range: $30–$1,200
A hose or cap is cheap; a radiator or pump is moderate; a head gasket is the high end.
The price depends on which cause it turns out to be — so confirm the cause before paying. Diagnose this for my exact vehicle →
Seeing this on your car? Get a diagnosis specific to your exact year, make and model — RedlineAi ranks the likely causes against real recall and complaint data, with an honest confidence score.
Diagnose my vehicle →Related OBD-II codes
If your car has stored a trouble code, these often accompany this symptom:
Related symptoms
This is general guidance, not a substitute for a hands-on inspection. Cost ranges are broad estimates to set expectations, not quotes. For safety-related issues, have the car inspected by a licensed mechanic before driving.