2009 Mercedes-Benz E320 Is Leaking Oil

Identifying the Causes of Oil Leaks in Your 2009 Mercedes-Benz E320 and How to Address Them

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Reviewed by
Aisha
Written by RepairPal Car Genius
Updated January 14, 2025
0%
80% chance it's the
Oil System Components
0%
20% chance it's the
Engine Gaskets
The most common reasons a 2009 Mercedes-Benz E320 is leaking oil are oil system component failure and leaking engine gaskets.
  • Oil System Components: A worn or damaged oil pump or filter can lead to low oil pressure, resulting in inadequate lubrication and potential engine damage.
  • Engine Gaskets: A worn or damaged engine gasket can lead to oil or coolant leaks, resulting in engine overheating or loss of lubrication.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a 2009 Mercedes-Benz E320 is leaking oil?

Common Repairs

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.

Oil pans don't wear out or break like other parts, they generally only need to be replaced because of external damage from an accident or an improperly tightened drain plug. The main symptom you will experience is an oil leak underneath the engine of your car. The oil that leaks from a damaged oil pan will range from dark brown to dark black. If the leak is large enough or occurs for long enough the oil level will be low enough to turn the oil pressure or low oil level warning light on.

The engine oil pressure warning light will come on if the engine oil pressure is low, or if the oil pressure sensor is faulty. In either case, engine power may be reduced significantly. The check engine light may also illuminate, and an on-board diagnostic (OBD) trouble code will be stored in the vehicle's computer.

What are the initial steps to diagnose an oil leak in a 2009 Mercedes-Benz E320?

To effectively diagnose an oil leak in your 2009 Mercedes-Benz E320, start with a thorough visual inspection of the engine and undercarriage. Look for any signs of oil accumulation, such as puddles or stains, which can provide immediate clues about the leak's location. Next, check the oil levels to determine if they are abnormally low, as this could indicate a significant leak that needs urgent attention. Pay special attention to the oil filter and drain plug, ensuring they are secure and free from any signs of leakage. Additionally, inspect the gaskets and seals, particularly the valve cover gasket and oil pan gasket, as these are common culprits for oil leaks. If the source remains elusive, consider performing a pressure test to identify hidden leaks or adding UV dye to the oil, which can help illuminate the leak under UV light. If these steps do not yield results, consulting a qualified mechanic may be necessary for a more comprehensive diagnosis. This methodical approach not only simplifies the process but also empowers you to tackle the issue with confidence.

What are the common causes of oil leaks in a 2009 Mercedes-Benz E320?

When dealing with oil leaks in a 2009 Mercedes-Benz E320, it's crucial to understand the common culprits that may be causing the problem. One frequent issue is the valve cover gasket, which can deteriorate over time, leading to oil seeping around the valve covers. Another potential source of leaks is the oil pan gasket, which may wear out or sustain damage, resulting in oil leaking from the engine's bottom. Additionally, the oil filter housing gasket can also fail, causing oil to leak in the vicinity of the oil filter. The oil cooler seals are another area to inspect, as they can fail and lead to leaks from the cooler itself. Lastly, the rear main seal, located at the back of the engine, is known to develop leaks as well. Addressing these leaks promptly is essential to prevent further engine damage and ensure optimal vehicle performance. Regular maintenance and inspections can help you catch these issues early, allowing for a more straightforward DIY repair process.

How urgent is it to address the oil leak in my 2009 Mercedes-Benz E320?

Addressing an oil leak in your 2009 Mercedes-Benz E320 is not just a matter of routine maintenance; it is a critical issue that demands immediate attention. An oil leak can lead to a significant loss of engine oil, which is essential for lubricating the moving parts of your engine. Without adequate lubrication, these components can suffer from increased friction, leading to severe engine damage over time. Additionally, neglecting an oil leak can result in decreased engine performance and efficiency, potentially causing overheating and further complications. Beyond mechanical concerns, an oil leak poses a safety risk by creating slippery conditions on the road, increasing the likelihood of accidents. Therefore, it is crucial to address any signs of an oil leak promptly to ensure the safety and longevity of your vehicle.

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2009 Mercedes-Benz E320 Oil Leak Causes & Repair Costs