Antifreeze (ethylene glycol or propylene glycol) is what keeps your engine from boiling in summer and freezing in winter. When it leaks, you risk an overheated engine - and the puddle on your driveway is dangerously sweet to dogs and cats. Here's how to spot a leak early.
Upper and lower radiator hoses crack with heat cycles. Look for swollen or wet spots, especially near the clamps. A new hose is $20-50 in parts and a 30-minute job for most cars.
Diagnose My Leak →When the water pump's internal seal goes, antifreeze drips from a small weep hole on the bottom of the pump. Listen for a whining or grinding sound from the front of the engine. $400-700 installed.
Diagnose My Leak →Modern radiators have plastic end-tanks that crack from age and pressure. Look for green or orange residue and a steady drip directly under the radiator. $300-700 installed.
Diagnose My Leak →A leaking heater core drips antifreeze into the passenger floor and fogs the windshield with sweet-smelling steam when the heat is on. Expensive job - the dash often has to come out. $800-1,500.
Diagnose My Leak →White exhaust smoke, milky oil, or coolant disappearing without a visible puddle - those point to a head gasket. The most expensive coolant problem at $1,500-3,500.
Diagnose My Leak →Describe what you're seeing and our AI mechanic will tell you what it is, how serious it is, and what it costs to fix - in seconds.
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A coolant leak that affects engine temperature can trigger these codes. The check engine light may come on once the system runs out of fluid.
Ethylene glycol tastes sweet, so dogs and cats lap it up willingly. Once swallowed it crystallizes in the kidneys and is fatal in tiny amounts. If you suspect a pet drank antifreeze, get to an emergency vet immediately.
They're the same thing. "Antifreeze" usually refers to the concentrated chemical (ethylene or propylene glycol). "Coolant" refers to the 50/50 mix of antifreeze and water that goes in your radiator.
For a short trip in warm weather, yes - water cools fine. But it freezes, boils at a lower temp, and offers no corrosion protection. Drain it and refill with proper coolant within a day or two.
That's a leaking heater core. The sweet smell comes from coolant evaporating off the core inside the dash. You'll also see fogging on the windshield with the heater on. Repair it before it ruins the carpet.
Tell our AI what you see under your car. You'll know what it is, whether it's safe to drive, and what the fix costs - in under a minute.
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