Symptom & fix Address promptly

Coolant leak (puddle or dropping coolant level)

A 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

high
Cracked or loose hoseRubber hoses harden and crack with age; a loose clamp leaks at the connection. A common, cheap fix.
high
Failing radiator or radiator capA corroded radiator or a cap that no longer holds pressure lets coolant escape.
medium
Leaking water pumpA worn pump seal weeps coolant, often leaving a trail near the front of the engine.
medium
Failing thermostat housing or gasketPlastic housings and gaskets crack with heat cycles and seep coolant.
low
Head gasket leakAn internal leak can burn coolant in the cylinders — serious, sometimes shown by white exhaust smoke.

How urgent is it?

Address promptly. Even a small leak needs a shop visit promptly — coolant loss rarely stays small, and the temperature gauge is your warning: if it climbs, stop. A fast leak or any overheating means stop driving and get help, because running low on coolant can quickly damage the engine.

Redline can’t determine from a symptom or code alone whether your car is 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 car →

Which cause is it on your car?

Start a case with what you’re noticing. Redline weighs these causes against your car’s evidence and names the check that would settle it.

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Related OBD-II codes

If your car has stored a trouble code, these often come with this symptom:

P0128 P0118

Related symptoms

Engine temperature runs hot or overheats Oil leak or low oil pressure warning Burning smell from the engine or vents

General guidance, not a substitute for a hands-on inspection. Cost ranges are broad reference ranges, not quotes. For safety-related issues, have the car inspected before driving.

Start a case

Seeing this on your car?

Every problem becomes a Case. Tell Redline what the car is doing: it shows what the evidence supports, what’s still missing, and what to check next, before you approve a repair.

Case updatedv2

Braking grind · 2016 Toyota Camry

“Inner pad ~1 mm. Outer pad 3 mm.”

Sticking caliper / slidePossible → Supported

Worn rotor onlyPossible → Less likely

Next: check the slide pins move freely before buying parts.

Example