Turbo Leaking Oil Into Intercooler [5 Easy Solutions]

Turbo leaking oil into intercooler is an issue you should never neglect. It will cause several problems like overheating the engine. A worn-out turbo seal, defective PCV system, and dirty air filter can cause the oil to leak from the turbocharger into the intercooler. 

If you don’t fix these issues, your engine gets overheated and decreases engine performance. Here in this troubleshooting guide, we will break down every reason responsible for leaking oil into the intercooler. So, keep reading till the end. 

Why Is Turbo Leaking Oil Into Intercooler?

Turbo leaks oil into the intercooler for several reasons. A worn-out turbo, a problem with the PCV system, and a turbo draining issue are some reasons that cause your turbo to leak oil into the intercooler. Besides, a dirty air filter and excessive crankcase pressure can be responsible for the turbo to leak oil. 

Below, we will break down each of the reasons that cause the turbo to leak oil into the intercooler. 

Note: You can also read Why oil coming out of the crankcase breather.

1. Turbo Gets Worn Out

A worn-out turbo, especially the bearings and oil seals, cause the oil to get into the intercooler. You can find a shaft with a couple of bearings in the turbo. Both the shaft and bearings get lubricated by the engine oil. Oil can easily make its way into the pressurized side of the turbo and be pushed into the intercooler when the bearings or oil seals wear out. 

2. PCV System Issue

Secondly, a PCV system can also be the caveat to leaking oil into the intercooler. All the vapor the PCV system recovers have a fine mist of oil. Typically, this vapor is routed back into the intact tract of the engine and can condense & settle down at the lowest point, which is generally the intercooler. 

3. Oil Draining Issue

Thirdly, the draining issue can also cause the oil to get into the intercooler. If the turbo is not old or worn out, we bet it is because of the oil draining problem. Make sure the oil drain line doesn’t get kinked and flow downward. Also, ensure the oil drain is of the right diameter. The diameter of the oil drain should be at least 3/4 of an inch. 

4. Dirty Air Filter

The dirty air filter can cause suction that pulls air out of the turbo seals. Consequently, it causes the oil to leak. Cleaning the air filter is a simple fix to this issue.

5. Excessive Crankcase Pressure

If it’s still leaking oil, you will need to do a compression test on your engine to ensure you don’t have excessive crankcase pressure coming up through your turbo. It’s a sign that you have blow-by in your engine and have excessive crankcase pressure if your turbo is leaking in high-boosted situations. Check out this tutorial to learn how to do a compression test.

Is It Usual To Have Oil In Intercooler?

At some points, the oil may have accumulated in the intercooler. But it’s not normal to have oil in there as the intercooler doesn’t have any oil by design or functional requirements. 

The turbocharger or supercharger runs at very high RPM and it gets lubricated by oil from the engine lubrication system. When the turbo seal gets worn out over time, it can leak some oil into the compressed air output from the turbocharger that can collect at the bottom of the intercooler. 

In this case, you must replace the turbo seals to stop the oil leakage. 

Is It Bad To Have Oil In Your Intercooler?

Yes, it’s not good to have oil in the intercooler as it causes the intercooler to fail and affects the air-fuel proportion of your engine. 

Generally, the function of the intercooler is to cool the air compressed by the turbocharger. It reduces temperature and increases the density of the air supplied to the engine. As the turbocharger compresses air, it gets hot. The oxygen content drops with the increase of the turbo temperature. By cooling the air, an intercooler allows denser and oxygen-rich air to the engine. As a result, it allows more fuel to burn to improve combustion and maximizes the engine power. 

If there is oil in your intercooler, it fails to work and cools the engine. Consequently, it reduces fuel combustion rate, decreases engine power, and causes your engine to overheat. 

How Do You Remove Oil From A Turbo Intercooler?

Follow the below steps to remove oil from a turbo intercooler. 

  • Start with removing the turbo intercooler from the vehicle. It may require you to remove the front bumper. Don’t forget to detach any piping or hoses from it. 
  • Next, pull out any grommets or seals to protect them from getting damaged by cleaning chemicals. 
  • Then, place a pan underneath the turbo intercooler to clean the oil and debris. 
  • Afterward, spray degreaser on the outside and inside of the intercooler. Leave the cleaner for 15 minutes to let it dry. 
  • Finally, rinse the intercooler with water to clean the gunks. 


How do you know when your intercooler is bad?

Overheating the engine, reduced engine power, and unnatural smoke from the exhaust system are some indications that let you know about a bad intercooler. 

What causes oil to get into the intake manifold?

A malfunctioned PCV valve, a blocked oil passage, air filter cleaner getting clogged, and defective piston rings are some culprits that cause oil to get into the intake manifold. 

How often should you clean your intercooler?

We recommend you clean the intercooler every 12 months to hold the optimal performance of your vehicle’s intercooler. 

How do you know if your turbo is leaking?

Grinding noise coming out of the engine, smoke from the exhaust, and engine light coming on are some symptoms that tell you about a leaking turbo. 

What does it mean when you have oil in your turbo?

It indicates too low oil pressure, which causes the internal parts of the turbo to wear out, and you get oil in your turbo as a result. 


You should fix the turbo leaking oil into the intercooler issue to let the intercooler work properly. Otherwise, you can’t get the optimum engine performance from the engine as it will make the engine hot. 

You can contact your mechanic to solve these problems if you don’t know how to repair the turbo leaking. 

About John M

John contributed as a technical head at an automobile company just 2 years after his post-graduation in Automobile Engineering. He loves to lead a free life, so he left his job & started blogging. Now, he does research on every automotive problem, part & product and seeks a better solution & best products & shares his findings with his readers to help them as well as to minimize their struggle.

Leave a Comment