Let’s consider your car stops running suddenly. You lift the front hood and see antifreeze liquid all over the engine, and it is smoking. Your mind might go crazy if you don’t know what it is and why it happens.
Well, antifreeze leaking with engine smoke indicates a leak with your cooling system. This leak allows engine coolant to escape and hit hot components, producing smoke. Common causes are a split radiator hose, failed water pump, cracked radiator, head gasket leak, or failed thermostat.
Fixing it requires finding and repairing the leak, flushing contaminated coolant, and refilling the system. Early detection can prevent major engine damage from this leak. Do you want to know more details about this issue? Read on!! I’ve got it all right below.
Antifreeze Liquid All Over the Car, Engine is Smoking: Why Does This Happen? [7 Hidden Causes]
As stated by Valvoline Global, antifreeze lowers the freezing point of the engine’s coolant liquid. This prevents ice formation of the coolant liquid in cold temperatures.
However, sometimes, the coolant (along with the antifreeze) can also escape from the pressurized cooling system. The reasons for this typically are:
1. Split or Detached Radiator Hose
Radiator hoses connect components together and tend to degrade over time. A hose split open or coming loose at the clamp will spew antifreeze rapidly.
2. Water Pump Failure
As the brand J.D. Power mentions, the water pump serves to circulate coolant through the engine and radiator. So, any wear, tear, and leaking seals on this can cause it to fail, dumping large amounts of antifreeze.
3. Cracked or Damaged Radiator
Plastic end tanks on radiators can crack over years of heating and cooling cycles. Once a crack forms, pressure sends coolant spraying out quickly.
4. Head Gasket Leak
A leaking head gasket allows antifreeze to escape into the cylinders or external crankcase. You’ll often see white exhaust smoke as coolant burns in the combustion chambers.
5. Corroded Freeze Plugs
Corrosion can eat away at freeze plugs in the engine block. Eventually, they fail, releasing coolant into the crankcase or externally.
6. Broken Reservoir Bottle
The plastic coolant reservoir mounted in the engine bay can crack and split due to age and heat cycles. This will drain all extra coolant onto the ground potentially.
7. Thermostat Failure
A stuck open thermostat prevents proper coolant circulation. This leads to overheating and pressure buildup. In turn, it can overwhelm hoses and gaskets, leading to leaks.
Antifreeze Liquid All Over the Car, Engine is Smoking: How to Fix It
Finding green, pink, or yellow antifreeze splattered around your engine bay or under the car is BAD NEWS.
The engine smoking at the same time makes it even worse. In this state, you might also hear an engine grinding noise at idle conditions. So, what to do?
Follow the below steps to stop the leak and get your car back up and running:
1. Turn Off and Allow the Engine to Cool Completely
Turn off your engine. Wait 30 minutes for everything under the hood to cool fully. With your phone camera, take a picture of the leaking area so you can find it again.
2. Identify the Source of the Leak
I recommend a systematic approach to finding the leak source:
- Conduct a visual inspection of all components in the cooling system.
- Use a drop light to illuminate underneath the vehicle.
- Look for fresh coolant dripping from components mounted on the engine block.
- Look for a milky contaminant in the dipstick.
Using these advanced detection techniques should lead you to the exact source of the leak. Expect the process to take 30-90 minutes in most cases.
3. Repair the Leak
Once you’ve identified the leaking component, you must repair or replace it. To stop the antifreeze leak, you’ll have to fix the following components as I have discussed them as the reasons for antifreeze leaking:
- Radiator damage: Replacement is best for cracks and pinhole leaks in the radiator components. After replacing it, make sure the replacement radiator has proper cooling capacity and connections.
- Radiator end tank damage: If this plastic tank leaked, fix it up with a special epoxy adhesive. Otherwise, radiator replacement is required.
- Rubber hose damage: Any visibly cracked, swollen, or leaking hoses should be replaced. Ensure length, diameter, and connections match the original when you replace these.
- Hose clamp leaks: Tighten any loose connections. Replace any clamps with rust or damage to prevent the recurrence of leaks.
- Water pump leaks: Leaks in this part mean full replacement. Replace the water pump with OEM or high-grade aftermarket options.
- Freeze plugs damage: Leaking or corroded freeze plugs also require you to remove and replace them. Use brass-made freeze plugs for the longest life.
- Head gaskets leak: Replace the head gaskets if they are allowing internal coolant leaks. This repair requires removing the cylinder heads. So, it’s best left to professionals.
- Thermostat housing damage: If you have cracked thermostat housing, you’ll have to replace it, too.
4. Flush the Cooling System
Drain and refill the cooling system 2-3 times to flush out all old contaminated antifreeze. Use distilled water when flushing to avoid mineral deposits. Flushing removes any particles that could clog coolant passages.
Remember, as reported by Universal Technical Institute, the coolant is the primary element that serves to transfer heat away from the engine. So, if you want to keep your engine cool, you have to routinely flush and refill the coolant liquid anyway. Therefore, do this chore even if you don’t have antifreeze leaking from your system.
Here’s a video guide to help you flush your cooling system.
5. Refill Coolant and Bleed Air
Top up the system with fresh antifreeze/water mix. Follow bleeding procedures to remove any trapped air:
- Make sure the engine is cool before opening the radiator cap.
- Open the radiator cap slowly to release any pressure.
- Fill the radiator and overflow tank to the proper level with fresh antifreeze coolant mixture.
- Start the engine and let it warm up to operating temperature with the radiator cap off.
- Rev up the engine slightly to circulate the coolant. Air bubbles will become visible, rising up through the radiator’s neck.
- Add more coolant slowly as needed to keep the level at the radiator’s neck. The coolant level will drop as trapped air escapes.
- When no more bubbles are evident, the system is fully bled. Top off any lost coolant.
- Reattach the radiator cap to seal the system.
Bleeding the system this way ensures no air pockets remain that could lead to localized hot spots and overheating damage.
6. Test Drive and Monitor Temps
Take the car for a short drive. Keep an eye on the coolant temperature. If it remains stable, the repair is likely successful.
If your car makes a whining noise when starting cold and still emits smoke, have a professional do the fixes again.
How Much Does it Cost to Fix a Coolant Leak From a Professional in the US?
The cost to fix an antifreeze leak can range quite a bit:
- Small hose leak: $150+
- Radiator leak repair/replacement: $350
- Water pump replacement: $400+
- Head gasket repair: $1200+
- Engine repair (if damaged): $3000+
Conclusion
Antifreeze leaking from your car’s engine (with smoking) indicates a problem with the cooling system. Common causes of this are a split radiator hose, failed water pump, cracked radiator, head gasket leak, or bad thermostat.
Fixing it requires finding and repairing the leak, flushing contaminated coolant, and refilling the system. Leaks happen mainly due to the age and wear of components like hoses, radiators, and water pumps.
If you want a professional to do the repairs, the cost will range from $150 for a hose to $3000+ for engine repair if damaged.
