Why is my Subaru eating coolant?
Subaru vehicles are known for their reliability and performance, but like any car, they can develop issues over time. One common problem some Subaru owners face is excessive coolant consumption, often referred to as "eating coolant." This issue can lead to overheating and engine damage if not addressed promptly. In this article, we’ll explore the potential causes of this problem and what you can do to fix it.
Common Causes of Coolant Loss in Subarus
There are several reasons why your Subaru might be consuming coolant at an unusual rate. Identifying the root cause is essential to prevent further damage to your engine. Here are the most common culprits:
- Head Gasket Failure: Subarus, particularly older models with the EJ25 engine, are notorious for head gasket issues. A failing head gasket can allow coolant to leak into the combustion chamber, where it is burned off, or into the oil system, contaminating the oil.
- Radiator or Hose Leaks: A damaged radiator or worn-out hoses can cause coolant to leak externally. These leaks are often visible as puddles under the car or as a drop in coolant levels in the reservoir.
- Faulty Water Pump: The water pump circulates coolant through the engine. If it’s failing, it can lead to leaks or insufficient coolant flow, causing overheating and coolant loss.
- Cracked Engine Block or Cylinder Head: In rare cases, a crack in the engine block or cylinder head can allow coolant to escape. This is a more severe issue that requires immediate attention.
- Heater Core Issues: A leaking heater core can cause coolant to escape into the cabin, often resulting in a sweet smell or foggy windows.
Each of these issues requires a different approach to diagnosis and repair. If you suspect your Subaru is losing coolant, it’s important to act quickly to avoid further damage.
How to Diagnose Coolant Loss
Diagnosing the cause of coolant loss can be tricky, but there are a few steps you can take to narrow down the issue:
- Check for Visible Leaks: Inspect the radiator, hoses, and under the car for any signs of coolant puddles or drips.
- Monitor Coolant Levels: Regularly check the coolant reservoir and radiator to see if the levels are dropping over time.
- Look for Contaminated Oil: If the oil appears milky or frothy, it could indicate a head gasket issue or coolant mixing with the oil.
- Perform a Pressure Test: A cooling system pressure test can help identify leaks in the system.
- Check for Exhaust Smoke: White smoke from the exhaust could indicate that coolant is being burned in the combustion chamber.
These diagnostic steps can help pinpoint the problem, but for a thorough inspection, it’s best to consult a professional mechanic.
What to Do If Your Subaru Is Eating Coolant
If you’ve determined that your Subaru is consuming coolant, here’s what you should do next:
- Stop Driving: Continuing to drive with a coolant issue can lead to overheating and severe engine damage.
- Consult a Mechanic: Bring your car to a trusted auto repair shop for a professional diagnosis and repair. At Kevin’s Autos, we specialize in Subaru repairs and can help resolve coolant issues efficiently.
- Consider Preventative Maintenance: If your Subaru is prone to head gasket issues, consider replacing the head gasket preemptively or using a high-quality coolant to reduce the risk of future problems.
Addressing coolant loss promptly can save you from costly repairs down the road. Regular maintenance and inspections are key to keeping your Subaru running smoothly.
Conclusion
Coolant loss in a Subaru can be caused by a variety of issues, from head gasket failure to radiator leaks. Identifying the problem early and seeking professional help is crucial to prevent further damage. At Kevin’s Autos, we have years of experience diagnosing and repairing coolant-related issues in Subarus and other vehicles. If you’re experiencing this problem, don’t hesitate to reach out to us for expert assistance.
Frequently Asked Questions
Why does my car keep eating coolant?
- Overfilling the cooling system
- A faulty radiator cap
- A worn-out radiator hose
- A leak that only occurs under certain operating conditions
- An undiagnosed cracked engine block or cylinder head, or a blown gasket
- Towing heavy loads
Why is my coolant disappearing with no leak?
Worn-out radiator cap: A worn-out radiator cap can allow coolant to slip through while driving, leading to coolant loss without a visible leak (1). Additionally, a clogged radiator system can block the flow of coolant, causing it to disappear without any visible leak.
Why is my coolant going down so fast?
If the coolant level is dropping and there is no external leak evident, then the coolant is probably leaking internally, into the engine. If the car has recently overheated then this could have caused the head gasket to fail. If it has, it could be leaking coolant into the combustion chambers.
Why is my Subaru using so much coolant?
Mostly, there is some trapped air within the system which works its way out and gets replaced with antifreeze. Naturally, the level in the overflow-tank will go down as this happens. Any Subaru dealership should be happy to top it up if you stop by and ask them to do so.
Can a bad thermostat cause coolant loss?
Coolant Leaks
As the engine overheats, coolant will overflow out of the thermostat housing. This means that coolant leaking out of your engine could be a sign that your thermostat has gone bad. It can also be a sign that you have a problem with your radiator hoses, the radiator itself, or the seals and gaskets.
Why is my coolant suddenly empty?
These are the most common sources of coolant leaks: There's a leak in the radiator, heater core or one of the hoses. The radiator cap is stuck open. Hot coolant leaving the system evaporates quickly.
Why is my coolant going down so quickly?
If the coolant level is dropping and there is no external leak evident, then the coolant is probably leaking internally, into the engine. If the car has recently overheated then this could have caused the head gasket to fail. If it has, it could be leaking coolant into the combustion chambers.
Why is my Subaru low on coolant?
Low coolant level: If the coolant level in your Subaru is consistently low, it's likely that there's a coolant leak. Overheating engine: A coolant leak can cause the engine to overheat, which can lead to serious engine damage.
How do I know if my Subaru water pump is bad?
For example, one common sign of a malfunctioning water pump is unusual noises coming from your Subaru's engine. More specifically, a squeaking, howling, or grinding noise may indicate that a water pump bearing has worn down, whereas a whining noise might signify a loose drive belt or broken water pump pulley.
How to tell if a water pump is bad?
The water pump has several gaskets that can be damaged or worn out over time. In this case, coolant may leak out and drip under the vehicle. If you notice coolant (in most cases green or red liquid) under the center front of your vehicle, it's time to check the water pump.
