Your Request for Help

Your name *Your contact phone *Your contact emailYour message

Select your make

Select auto repair shop

Your preferred contact Info

Issues

Your concern might be complex to diagnose and may require additional equipment to pinpoint the cause. In this case, you'll receive Digital Inspection results plus a quote to perform deeper diagnostic/test procedures.

Home / Symptoms / Car Leaking Oil

Four common causes for a vehicle Leaking Oil and their related parts.

If you are short on time and want to fast-track the process to professional help, click

Is Your Car Leaking Oil?

It’s leaking oil because there might be sealing issues in the oil pan, valve cover, or oil filter. It can also be that the drain plug is loose, or some of the many seals are worn out, like the crankshaft seal.

The engine works hard to power your automobile. It needs oil to lubricate many moving parts and keep it running smoothly. Maintaining the proper level of clean engine oil is one of the primary responsibilities of maintaining your vehicle. But, if there is a leak somewhere, the oil escapes the pan quickly.

Oil leaks could be the result of a poorly executed oil change. If that's the case, the fix might be as simple as tightening the drain plug. However, oil can also escape from several valves as it runs through your engine, which is more complex.

Watch out: Keeping oil in your engine is vital. If levels get too low, your engine catastrophically damages itself as it runs. This risks a breakdown or extensive repairs. Also, engine oil is a harmful substance. So, leaking oil might damage the environment and seep into groundwater.

The most common causes for a vehicle leaking oil

The most common causes for the car’s oil leaking:

Oil filter leaking: The oil filter is a small box connected to your engine system that sucks oil in, cleans it and releases it back into the system. The filter has seals around it to ensure the oil passing through doesn't escape. However, these seals can fail, allowing oil to seep out.
Valve cover leaking: The valve cover is a component on top of the engine that protects many of the internal combustion components like valves, camshafts, chambers, etc., that are constantly working with oil. Therefore, the valve cover also keeps the oil shut inside. However, if the valve cover fails, oil might start escaping through gaps and cracks.
Loose drain plug: The drain plug is the bolt-like part that you rotate and remove so the oil can start flowing out during an oil change. It's located under the vehicle, under the oil pan. Then, when putting it back on, you must ensure it's tightly put. A loose drain plug will allow oil to slowly seep out and escape.
Crankshaft seal leaking: The crankshaft sits inside the engine and it controls when the engine's pistons move up and down during the combustion process. The crankshaft rotates in a way that transfers the piston's movements to the wheels, making your vehicle's performance better. However, since the crankshaft works directly with oil, if it fails and loses sealing, you might start noticing leaks.
Timing cover leaking: The timing cover is a protective shield housing belts and chains that rotate many of the engine's pulleys, becoming essential for various systems. The timing cover also has oil so it can keep the chains under it lubricated. Therefore, if the timing cover fails, gets cracked, or loses sealing, it'll allow oil to leak out.
Oil pan leaking: The oil pan is the ultimate oil container that sits under your vehicle. Much of the oil running inside your vehicle comes from and returns to the oil pan. However, the oil pan can suffer damage, rust, or lose sealing, allowing oil to leak out.

Frequently Asked Questions

Is there blue smoke coming from under the hood?

You may also notice an oil puddle on the ground under the vehicle or see that the engine oil is low.

The oil pan is the reservoir bolted to the bottom of your engine block that your engine draws lubrication. After your engine runs, the oil returns to the pan. Since the exhaust system runs alongside or across the oil pan, you will see blue smoke from oil burning on the hot exhaust if the oil pan gasket leaks oil.
Do you have visible signs of oil leaking under your vehicle after an oil change?

You may also notice black smoke under the hood or an oil puddle on the ground under the vehicle.

When a vehicle's oil filter seal is installed correctly, it bonds to the oil filter adapter. Over or under-tightening can cause oil leaks. When oil filters are changed, sometimes the seal sticks to the adapter, and it doesn't get noticed, resulting in two gaskets where there should be one. When the oil pressure builds, one of these seals will blow and cause a severe oil leak.
Is the valve cover covered in oil?

You may also notice a burning smell coming from the vehicle or see the "check engine oil" light lit on the dashboard.

The valve cover keeps your oil in the right place and protects it from dirt and debris. When it fails, you'll see oil on the valve cover. Since the engine's crankshaft casing is pressurized, if this valve fails, it will suck in air that might be contaminated with debris as it runs. This dirty air can damage vital engine components and cause your engine to sound or feel like it's running rough.
Is there oil dripping off the oil pan plug?

You may also notice black smoke under the hood or an oil puddle on the ground under the vehicle.

The drain plug is at the very bottom of the oil pan. Since this plug is removed and fastened again with every oil change, its seal wears over time. Therefore, it may need to be replaced if you see it leak oil or be too tight or loose.
Do you have an oil spot under your car where you park?

You may also notice that the "check engine" light has come on, or the engine might be running rough.

Seals on the front and back of the crankshaft keep dirt and debris out of the engine oil. Because the crankshaft is pressurized with oil, it is forced against these seals as it runs. If the seals become worn, the oil will start seeping and spotting underneath the vehicle. You'll notice it under your car when you move it after it has been parked.
Is your engine oil low on the dipstick?

You may also notice that some suspension components are soaked in oil or find an oily spot towards the rear of the car's underside.

The timing cover is at the front of the engine and houses the timing chain tensioner and cam phasers. Since the timing chain is constantly in motion, it forcefully throws oil against the timing cover and gasket. Therefore, when the timing cover gasket fails, your engine can lose a lot of oil quickly. You will be able to see the loss of oil measured on the dipstick.

Typical fixes to address the cause(s)

These are typical processes and repair services that fix a check engine light issue

The most common cause: Oil pan leaking

The most common reason for a car leaking oil is due to an oil pan leak. The oil pan is a container that holds much of your vehicle's oil, similar to the gas tank holding the fuel. The oil tank is commonly the cause of oil leaks since it sits under the car and can get banged up depending on if the vehicle hits a pothole or gets into a recent accident.

Symptoms it causes: Apart from the oil leaking you might notice squealing sounds, engine overheating, oil pressure warning light on the dashboard, etc.
High risk of priority: A leaking oil pan eventually leads to your vehicle's engine receiving low oil amounts. If your vehicle starts running low on oil, most of its internal components suffer extra friction, leading to catastrophic damage.

How exactly does the oil pan leak?

The oil pan is incredibly resilient and well-protected in most modern vehicles. However, since the pan is located under the vehicle, driving in rough terrain and hitting the vehicle's floor on potholes or road debris, can damage it. Consequently, the pan might crack, dislodge, and start leaking oil.

Go safe: Ask for a mechanic to inspect your vehicle's oil system to investigate if the oil pan is leaking due to surrounding components and if there’s further damage to check out. Many shops do transparent vehicle inspections and lay out your options after investigating your vehicle’s conditions.

What’s a vehicle inspection? It’s “detective work” on your vehicle, checking its systems to see if anything prevents the car from working as expected. In this case, mechanics examine different parts of your vehicle to track if anything is causing the oil pan to leak. They’ll also check the condition of components during their inspection, noting which are causing the problem and which got affected by it, recommending to replace them in order of priority.

Transparency example in a leaking oil pan service

An oil system inspection is the most transparent process to understand why your vehicle’s oil pan is leaking. This is because many components surrounding the oil pan, oil filter, and oil hoses can have a say in the issue, indicating the real culprits that caused it all.

Let’s read an example of how this kind of inspection helps to service a leaking oil pan.

A customer dropped off their vehicle after seeing black smoke rise from under it while driving in stop-and-go traffic on the freeway. They thought it smelled more like burning oil than burning wire or rubber.

On the test drive, the mechanic confirmed the burning oil odor. However, they did not notice any smoke coming from under the hood.

During the vehicle health inspection, the technician observed oil around the oil pan and saw it dripping onto the exhaust. To further inspect the issue, the customer authorized the shop to degree the engine (synchronizing the camshaft to the crankshaft) to verify where the leak was coming from.

The technician was able to degrease the underside of the engine. After drying off the bottom of the engine, the technician ran the vehicle on a lift to determine the origin of the oil leak and found it was coming from the oil pan gasket. The oil pan must be removed to replace the gasket, and they will also have to drop the exhaust.

Oil pan leaking

In this case, the mechanic put the “Immediate Action” tag on the evaporator temperature sensor.

Similar Symptoms

Below are just a few examples of typical Symptoms and Fixes your car might be experiencing

Four common causes for a leaking coolant from the vehicle and their related parts.

Is Your Car Leaking Oil?

The most common causes for a vehicle leaking oil

Frequently Asked Questions

Is there blue smoke coming from under the hood?

Do you have visible signs of oil leaking under your vehicle after an oil change?

Is the valve cover covered in oil?

Is there oil dripping off the oil pan plug?

Do you have an oil spot under your car where you park?

Is your engine oil low on the dipstick?

Typical fixes to address the cause(s)

The most common cause: Oil pan leaking

How exactly does the oil pan leak?

Transparency example in a leaking oil pan service

Similar Symptoms

Why is My Car Leaking Coolant?

Why is My Car Leaking Water?

Why is My Car Leaking Gas?

Why is There Red Fluid Leaking from My Car?

Why Is My Car Battery Leaking?

Why Is My Evap System Leaking?

Why Is The Radiator in My Car Leaking?

Why Is My Car Leaking Power Steering Fluid?

Why Is There Pink Fluid Leaking From My Car?