The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.
When the head gasket begins to fail, the engine may have no symptoms at all. They only begin to occur when the leak has reached an engine oil passage, engine coolant passage or the engine cylinder.
When that happens, the engine may be very difficult to start, and run roughly when idling. There may be oil or coolant leaking, and the engine may begin to overheat, or at least run hot. At this point, there may be coolant in the engine oil pan — this will look creamy and lighter in color than the oil. Also, the radiator or engine coolant reservoir may have a gurgling sound, the presence engine oil, or smell of combustion. And the check engine light will come on.
The coolant being burned in the engine will produce white exhaust that smells sweet, like engine coolant. When the head gasket fails completely, the engine will overheat within minutes of starting, will stall and then won't restart.
A failing heater core may cause the car's interior to smell like engine coolant. The smell will become worse when the heater is turned on. The engine may also begin to run hotter until the vehicle is repaired.
The worst-case scenario is the engine overheating, which can cause extensive engine damage.
If the heater core is clogged, the air that blows when the heater is turned on will not be very hot.
Problems with the intake manifold gasket can create the following symptoms:
» LEARN MORE: Intake manifold gasket symptoms
A failing radiator can cause the engine to run hot or overheat. Most radiators are made of metal and plastic. The plastic parts can become brittle and crack over time, causing a leak of coolant (typically green or pink in color). All manufacturers have a recommended service interval for coolant renewal. As the coolant ages, the additives breakdown and being to form solid deposits. These deposits will build up in the passages of the cooling system and will eventually clog components, including the radiator. A leaking or clogged radiator must be replaced. Some automatic transmission cars will also have a transmission cooler integrated into the radiator. Lines going to and from the transmission circulate transmission fluid to help cool the transmission in heavy duty applications such as towing or off-roading. If this integrated cooler fails, it can allow transmission fluid and coolant to mix. This will causing shifting issues in addition to overheating.
A coolant leak may be noted from the hoses. Coolant hoses can be damaged by oil leaks, or age. This will lead to swelling or cracking, it is suggested to replace the hoses before they begin leaking to avoid potential overheating.
The bad thermostat can cause two different sets of problems, depending on whether it's stuck open or stuck closed.
A thermostat that is stuck open can cause the engine to run colder than normal and turn on the check engine light. It may also cause poor fuel mileage and the heater to blow cool air.
A thermostat that is stuck closed will cause the vehicle to overheat. If a new thermostat doesn't resolve engine temperature problems, the cooling system needs to be checked for other issues.
» LEARN MORE: Signs of a bad thermostat, and how to fix it
If a vehicle is overheating, a bad thermostat could be the problem, and a damaged thermostat housing is more likely to produce a coolant leak, either from a cracked or warped housing or a failed seal to the engine. The thermostat housing can be made of metal or plastic. And the housing can be a stand-alone part that is separate from the thermostat, or (on later model vehicles) can be integrated with the thermostat and replaced as a single unit.
The two most common signs of a bad pump are leaks and noises.
Leaking water pumps can result in damage to the drive and timing belts, and cause the engine to overheat. A failed water pump can be caused by other problems in the cooling system, such as a bad thermostat, radiator or head gasket.
To effectively diagnose a coolant leak in your 2012 Chevrolet Malibu, start with a systematic approach that prioritizes simpler checks before moving on to more complex diagnostics. Begin by inspecting all hose connections within the cooling system, as loose or damaged hoses are often the easiest culprits to identify and fix. Next, examine the radiator for any visible signs of damage or leaks, as this component is frequently associated with coolant loss. Following that, assess the water pump for any indications of leakage, since a malfunctioning pump can also contribute to coolant issues. It's also crucial to be vigilant for symptoms of a failing head gasket, such as engine overheating or unusual exhaust smoke, which may not present obvious signs but can lead to significant coolant leaks. If these initial checks do not reveal the source of the leak, consider utilizing a coolant pressure tester, which can help pressurize the system and pinpoint leaks more effectively. By following this structured diagnostic approach, you can efficiently identify and address coolant leaks in your vehicle.
When dealing with coolant leaks in a 2012 Chevrolet Malibu, it's essential to understand the common culprits that may be at play. One of the primary causes is a damaged radiator, which can develop cracks or corrosion over time, leading to leaks. Additionally, worn-out hoses are another frequent issue; these hoses transport coolant throughout the engine and can deteriorate, resulting in leaks. A faulty water pump is also a potential source of coolant loss, as it may fail to maintain proper pressure, causing coolant to escape. Furthermore, loose or damaged hose clamps can prevent a secure seal, allowing coolant to leak from the connections. In more severe cases, a cracked engine block can lead to significant coolant loss, while a leaking heater core may cause coolant to seep into the cabin of the vehicle. Addressing these issues promptly is crucial to avoid overheating and potential engine damage, making regular maintenance and inspections vital for any DIY enthusiast looking to keep their Malibu in top shape.
Addressing a coolant leak in a 2012 Chevrolet Malibu is an urgent matter that should not be overlooked. Ignoring a coolant leak can lead to severe overheating, which poses a serious risk of engine damage and can result in costly repairs. Additionally, a coolant leak may signal deeper issues within critical components such as hoses, radiator caps, or head gaskets, all of which require immediate attention to ensure the vehicle operates efficiently. Delaying repairs can exacerbate the problem, leading to a significant loss of coolant that compromises the entire cooling system, ultimately jeopardizing the engine's integrity. For the safety of both the driver and passengers, as well as the longevity of the vehicle, it is essential to address any signs of a coolant leak promptly.
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