3 Reasons Why Your Car Leaking Oil When Parked (You Must Fix That ASAP)

Written by Victor

In this blog post, we look into the critical topic of why your car might be leaking oil when parked and why addressing it is a top priority.

Is your car dripping oil?

After parking it in the driveway overnight, you may have noticed a dark puddle beneath your car. Or perhaps you spotted a telltale drip while you were out on a long drive. If you’re seeing your car leaking oil, it’s crucial to take action immediately. After all, oil is essential for keeping your engine running smoothly.

The first reason why car leaking oil when parked is oil pan leaks. They are usually caused by a degradation of the gasket that sits between the pan and engine block, overtightened drain plug, a faulty drain plug gasket, or rust on the metal surface of the oil pan. A valve cover gasket leak is another reason, often caused by age or excessive heat exposure. The last, less common reason is leaks in the camshaft or crankshaft seals.

Huge panoramic roof on a vehicle, view from inside the car

What is Engine Oil and Why it Can Leak From the Engine?

Engine oil is a lubricant that helps to keep moving parts in the engine working smoothly. Over time, engine oil can become dirty or degraded and may need to be replaced.

Additionally, the presence of water in engine oil, often due to coolant leakage, can create an emulsion that diminishes the oil’s effectiveness and potentially harms the engine.

However, if oil leaks from the engine, it can cause damage to the engine and reduce its efficiency.

Engine oil leaks can be caused by several things, including a faulty gasket or seal, a cracked engine block, or an improperly installed oil filter. Sometimes, an oil leak may not be serious and can be fixed with a simple repair.

However, if the leak is severe, it may require expensive engine repair.

In the following paragraphs, we’ll discuss the main reasons for oil leaks in your car:

Reason 1 – Engine’s Oil Pan

The car’s oil pan is a metal or plastic container that holds the motor oil in a car’s engine. It is usually located at the bottom of the engine block, beneath the crankshaft. The oil pan is mounted to the engine with bolts, and in between, it’s sealed with a gasket.

It also has a drain plug that allows the oil to be removed for changing. The oil pan usually has a dipstick to check the engine’s level of oil.

Reasons for oil pan leaks

  1. The most common reason for an oil pan leak is a degraded gasket. The oil pan gasket seals the gap between the oil pan and the engine block. As the gasket ages, it dries out and cracks, allowing oil to seep through.
  2. Major oil leak can also be caused by a oil pan plug (drain plug) that has been overtightened or by a faulty drain plug gasket. If the drain plug gasket isn’t replaced during an oil change, it can develop leaks.
  3. Lastly, rust on the metal surface of the oil pan can also cause leaks. When rust deteriorates the metal, it creates gaps that allow oil to escape.

If you notice your car’s oil level is low or there is a gar under your vehicle, it’s essential to have your car checked by a mechanic to determine the cause of the leak.

Reason 2 – Valve Cover Gasket

The valve cover gasket is a thin, flat piece of rubber that sits between the valve cover and the cylinder head, and it helps to prevent oil leaks. It’s usually located at the very top of the engine.

Reasons for valve cover gasket leak

Over time the gasket can become damaged or worn out, causing oil to leak from the engine. In some cases, the problem may be caused by age or heat, but sometimes it results from improper installation.

Fortunately, in most cases, the problem can be resolved with a simple replacement of the gasket. However, if the damage is severe, replacing the entire valve cover may be necessary.

A new gasket is relatively inexpensive and a simple repair that can save you a lot of money in the long run.

Reason 3 – Camshaft and Crankshaft Seals

The engine is equipped with seals at various points where moving parts protrude from the engine block to prevent leaks. The most common types of seals are camshaft seals and crankshaft seals.

Camshaft seals are located at the base of the camshaft, where it protrudes from the engine block.

Crankshaft seals are located at either end of the crankshaft, where it extends through the engine block.

Both types of seals work to keep oil from leaking out of the engine, ensuring that it remains properly lubricated.

When to replace camshaft and crankshaft seals

When your engine’s timing belt or gearbox needs to be removed, it’s also a good idea to replace the camshaft and crankshaft seals. These seals are relatively inexpensive, and they can help prevent leaks.

Over time, these seals can age and become less effective. Replacing them at the same time as the timing belt or gearbox can help save time and money in the long run.

If you decide to save a couple of bucks on these seals during timing belt or gearbox removal, you may end up paying for the same job again later on, as their replacement requires removing these parts.

If your engine is driven by a timing chain instead of the timing belt, the same rule applies to the chain cover gasket.

Other Less Common Oil Leak Reasons

In addition to the more common causes of oil leaks, there are a few other potential culprits that should be considered:

  1. Improper installation of the oil filter. If the filter is not correctly seated, it can cause an oil leak;
  2. Transmission axle seal leak. This type of leak is often caused by wear and tear on the seal itself;
  3. A head gasket leak can also lead to an oil leak. Head gasket leaks are often caused by overheating, which can damage the gasket and allow oil to escape. This type of leak is typically more serious than others and should be repaired as soon as possible;
  4. If you have a turbocharged engine, there are a few additional places you should check for oil leaks. The air hoses from the turbo to the intercooler can develop leaks over time, as can the gaskets around the turbo itself;
  5. Loose or damaged oil filler cap can allow oil to escape;
  6. Leaks in the power steering or brake fluid lines.

As such, it is important to be aware of all the potential causes of oil leaks in order to diagnose and fix the problem as quickly as possible. If you are unsure of the cause of an oil leak, it is always best to consult with a professional mechanic who will be able to properly diagnose and repair the issue.


All in all, if you are experiencing an oil leak in your car, it is important to take care of the issue as soon as possible.

The three most common reasons for a car leaking oil when parked are due to problems with the damaged oil pan, valve cover gasket, and camshaft and crankshaft seals. While these are the most common issues, other less common causes for oil leaks should also be considered.

Have you been able to identify what is causing your car to leak oil? Write in a comment below and let us know!

Republished: February 3, 2023 - Originally published on August, 25 2022


Victor is a car technician with 10 years of experience in the auto repair industry. He's an enthusiast of blogging and he likes nothing more than spending his weekends working on his car. Victor is always up for a new challenge, and he loves learning new things.

Related Articles

How Often Should You Wash Your Car – A Detailed Guide

How Often Should You Wash Your Car – A Detailed Guide

How Often Should You Wash Your Car - A Detailed Guide. Cars are significant investments and require a ton of money to maintain - from replacing filters and belts to changing oil and brake pads. One of the best ways to maintain a car is through a regular wash. However,...

4.3/5 - (26 votes)
Was this article helpful?
Looking for an Auto Glass Replacement?

Looking for an Auto Glass Replacement?

Please take a moment to complete the form below, and we'll promptly perform a parts check to deliver an accurate quote for your vehicle.

Thank you for submitting your request! Our support team has received your message and will get to work right away.