Honda Oil Dilution – How Serious Is This Problem?

Are you planning to purchase a Honda and you heard about the Honda oil dilution problem and you want to learn if your potential vehicle has this problem? If this is the situation that you are in, then you are at the right place because this article will be all about the Honda oil dilution problem.

• Honda 1.5 Engine Overview
• Honda 1.5 Engine Specs
• Applications Of The 1.5L Honda Engine
• Honda Engine Oil Dilution
• Other Common Problems & Issues
• Final Conclusion
• Frequently Asked Questions (FAQs)

Getting yourself properly informed before you jump out there on the market is key. There are simply a vast number of cars and almost all of them have problems more or less. Some of these problems like the oil dilution issue can be damaging for your engine as well as for your budget since fixing the issue costs a ton of money to do so.

That’s why learning the potential issues will give you that extra edge when it comes to making the right decision on purchasing the vehicle or not. Since buying a new car is not grocery shopping but an investment. And it’s best for you that this investment pays off. If else, you will probably get furious that you have spent all of your money on a basket case. And we are going to help you out in making the right decision. This article will be all about the 1.5L engine.

First, we are going to learn the basics of this engine and the specs. Then we will learn in what cars was this engine used. Then we will discuss the Honda oil dilution problem and what Honda did to fix this problem here in the US and abroad. Later, we will discuss other problems that this engine has. So, without further ado, let’s get into it.

Honda 1.5 Engine

So, before we discuss the Honda oil dilution problem. Let’s first cover some of the basics about the 1.5L engine that is made by Honda. Since this engine is the one that is affected by the oil dilution and the only engine that we are going to cover in this article to simplify things.

This engine was introduced by Honda with the 2016 Civic. The idea with this engine was that with the help of downsizing it makes the same power numbers. So, what is downsizing? Downsizing is a term used in the car world to explain the shift from big displacement engines to smaller displacement internal combustion engines.

But when you downsize you lose power, right? There is no replacement for displacement? Or no? Well, not quite, there is still a replacement for displacement. Even though this replacement is not that sufficient in some areas you can still feel how the car simply is not even similar in performance in comparison to a car with a bigger displacement engine.

Still, there is a replacement for displacement. And this replacement was made possible by forced induction. Namely, turbocharging. Almost all carmakers shifted to turbocharged engines in recent years. Was this a smart move? Not necessarily. But it is what it is. We are witnessing a world that is moving towards better sustainability, as they say, this is one of the things that will move us forward. No car guy probably approves this shift. But that’s how things go right now.

So, Honda has introduced this engine to replace the naturally aspirated engines (to find out more, check out our explainer on what does naturally aspirated mean) and this engine delivered a good performance. But more on that in the following chapter where we will cover the specs of this engine and later the Honda Oil dilution problem.

Honda 1.5L Engine Specs

Now before we discuss the problem with the Honda oil dilution. Let’s first focus on the engine specs of this specific engine. Specs are always welcomed to know if you are in the market for a Honda and you want one specifically with this engine. So, let’s cover them real quick.

The Honda 1.5L as its name implies is a 1.5L engine manufactured by Honda. This engine is a straight-4 engine design. What is peculiar to this engine is that the exhaust manifold is cast into the cylinder head. A really strange design I must admit and probably the only engine in the world running on this spec.

This head design also has some benefits like helping the engine to reach up to temp faster. But this way is also cheaper to make the engine.

The block of the engine, as well as the head, are made out of aluminum and this engine implements direct fuel injection as well as a double overhead camshaft design with 4 valves per cylinder.

The bore of the cylinder is 2.87mm and the stroke is 3.52 inches with an overall displacement of 1489cc or 91.4cu. As you can see, pretty tiny engine overall.

The compression ratio of this engine is high at 10.6:1. The oil capacity of the engine is 3.7 quarts of oil. So, you can expect cheap oil changes.

The power numbers that this engine is making are between 174 and 205hp depending much on the application. The torque numbers are also between 162lb-ft and 192lb-ft of torque.

Overall, although small, it is a really peppy engine. All this is made possible by the turbocharger that is installed on it. This turbo makes it able to produce so much power. But what about the Honda oil dilution? More on that in a bit.

Honda 1.5L Engine Applications

Now before we learn the Honda oil dilution problem. Let’s first learn more about what cars are using the 1.5L engine. Since this is the starting point if you are in the search for a car with this engine. You need to know the applications of this engine to be able to find a vehicle for you with the 1.5L. So, what are the applications? Let’s elaborate.

The 1.5L is mostly found as a standard engine in the Honda Civic and the Honda Civic Si (to learn more, check out our guide on are Honda Civic reliable). The Civic Si has the most potent engine option. Meaning that the engine on this model is tuned to deliver up to 205hp with no sweat. So, if you are on the market for a Civic that delivers a lot of power. Then the Si might be the right one for you. The earliest Civics that got the 1.5L engine were built in 2016.

This engine also found its way into the Honda CR-V which is a mid-size SUV. In fact, the 1.5 is one of the most popular engines in the CR-V with more than a few hundred thousand cars sold. This engine in the CR-V produces about 182hp. A bit more than the base Civic. Since it is a heavier vehicle, this is quite understandable. In addition to the CR-V, this engine was also included in the Acura CDX. The CDX is basically a rebadged CR-V under the Acura name (fun fact, go check out our guide on how to debadge a car).

This engine also found its way into the bigger Honda Accord. Namely, as a base engine of this model. Personally, I think that the Accord is too big of a bite for the 1.5L engine and the Accord seems to be a bit underpowered with this motor. But that’s what you get as the standard.

Honda 1.5L Engine Problems

Now let’s talk more about the problems of this Honda engine with the main focus on the Honda oil dilution problem.

Not that we are not going to talk about all of the problems that this engine has but our main focus will be on the oil dilution and how Honda is tackling this problem that bothers a lot of car owners and makes their life difficult. So, if you want to learn more, follow along.

Honda 1.5L Oil Dilution Problem

Now let’s get down to business and talk more about the Honda oil dilution problem. What is oil dilution in general? Oil dilution in the simplest definition is when the oil gets mixed with gasoline and then the oil is diluted. Meaning that the engine is definitely not getting the right lubrication and also not producing the right performance.

This situation is not ideal. But also it’s not the end of the world. Since everything is good with the engine. But somehow gasoline passes through the cylinder walls and ends up in the oil compartment. Polluting the oil in the process and ruining the engine performance. A small oil dilution is normal. But what happens in the 1.5L it’s not.

This problem is by design. To be more precise, this problem happens because the gasoline is not ignited well inside of the cylinder at below-freezing temperatures. The gasoline simply sticks to the cylinder walls. Then as the pistons move, they bring the gasoline down to the oil compartment.

The engine needs some time to heat up and burn the gasoline well. In this case, the cold engine block of the 1.5L is causing this problem. Once the engine warms up, everything works well. But the gas which is already there will mix with the oil and you will experience the Honda oil dilution problem.

This problem often happens in areas of severe cold temperatures. More precisely in winter when temperatures are extreme. The 1.5L simply doesn’t work well in cold and the oil dilution is one of the consequences of this. Especially if you are doing some short trips. The engine simply can’t heat up well and Honda oil dilution happens.

Honda Oil Dilution Symptoms

So, we learned about the Honda oil dilution problem. Now let’s see what are the symptoms that you will probably face whenever you experience a problem like this in a Honda 1.5L car.

The first and most obvious symptom is the misfire in the engine. This engine is not happy when it works at really low temperatures. And precisely these misfires are making things worse. Because the engine when it starts at cold temperatures is misfiring when it reaches the operating temperature. These misfires mean that the gas is not burnt completely and will come down into the oil pan and dilute the oil.

Another symptom connected with this problem is the loss of power. This is understandable since you are experiencing misfires, it is logical that the power will be down as well. Nothing too serious but in extreme situations, it will be noticed. In addition to this engine, stalling is also present in extreme cases of oil dilution when the oil level is way too high and is impairing the engine to work right.

Luckily for you. Most of the owners didn’t report very serious problems with the dilution. Yes, there is a mixture of oil and gas. But nothing that significant. The important thing when you have this engine is to do oil changes more regularly. But more on that, we are going to cover later in the article where we will learn about the ways you can try to avoid this problem of Honda oil dilution.

Now, let’s see what Honda did to sort this problem in the US and Canada since these two countries are one of the most affected by the Honda oil dilution.

What Did Honda Do To Fix The Oil Dilution In Canada

So, we learned what is Honda oil dilution and now let’s see how Honda is tackling this problem in Canada. If you are from Canada and you are reading this. This will be very useful for you.

More precisely, Honda has decided to allow the vehicle owners to get a warranty extension for certain engine components. The affected models were the 2017-2018 Honda CR-V as well as the Honda Civic produced from 2016 to 2018. The warranty extension was up to six years after purchase with no limit on the mileage.

A quite fair move by Hond to help their customers who purchased one of their cars. But was this the case with the US? Let’s find out in the next chapter.

What Did Honda Do To Fix The Oil Dilution In The USA

So, we learned what is Honda oil dilution and what Honda did in Canada for their customers by extending the warranty of the affected cars. But what Honda did do for the US market?

For the US, they took another approach. This approach affected only owners in five states where temperatures are extremely cold. Namely, North and South Dakota, Wisconsin, Maine, and Minnesota. But it wasn’t too soon that more than 21 states were granted the same benefit. And since recently this campaign spread across the whole country. But what does this move by Honda include?

Well, it includes an extended powertrain warranty for vehicles that are less than 6 years old. This campaign includes checking your car at the dealership and performing a software update.

In addition to this, there was replaced the drain plug washer and a fresh oil change. With this software update, Honda models with this engine reach up to temperature sooner and this problem becomes less of a problem if you know what I mean. Since the engine gets hotter sooner, there will be less gas that will pass to the oil compartment and dilute the oil.

So, if you have a Honda that was produced from 2016 to 2018 with this engine, you are highly likely that you are eligible to sort the Honda oil dilution problem at their dealerships. Just take your car there and make sure that they sort it out.

What To Do To Avoid This Problem

So, we learned what is the Honda oil dilution, why it happened, and what did Honda to fix it. Now let’s see what you can do to avoid this problem in general.

Even after software updates, there could be some dilution. So, what are the recommended things that you can do to make sure that you don’t end up with a damaged engine?

The number one thing is to perform regular oil changes. On these engines, the oil change recommendation is to be done every 9,000 miles. But if you want to play it on the safe side. The best would be to flush your oil every 6,000 miles.

Or, if you are really into it, you can take a sample of your oil to a lab. Then they will check based on the mileage of how much the oil is diluted and will specify to you the right intervals that you should follow if you want to avoid this problem becoming worse and possibly damaging your engine.

Another good tip when it comes to Honda oil dilution is to take your car more often on longer trips. This will guarantee that the engine heats up well and also performs as it should.

Still, pay a visit to your local Honda dealership and see what they have to say on this topic and whether or not you are eligible to participate in this service of theirs that involves updating the software to help fight this problem of Honda oil dilution. This would be your best bet.

Other Honda 1.5 Engine Problems

We learned more about the Honda oil dilution. Now let’s discuss some other problems that this engine has. And frankly, there are a few of them that are worth mentioning.

Not something scary but only for you to know that they are there and are basically in every one of these engines. So, what are the other problems with this engine? Let’s elaborate in-depth in the following chapters.

Honda 1.5 Engine Problems #1: Carbon Buildup Because Of Direct Injection

Another common problem with this engine except the Honda oil dilution is the carbon buildup in the intake ports.

This is something that all of the direct injection engines are struggling with. And this problem is by design. In classical MPI injection, the fuel is cleaning the ports when it falls down in the cylinder.

With direct injection, the fuel is injected in a different manner with the help of a high-pressure pump and injectors. Meaning that the intake ports are not touched. So, the carbon keeps accumulating on them and creates a real mess.

The carbon buildup can be so large that could make the valves get stuck and experience problems like misfires, loss of power, and other things that you don’t want to experience.

That’s why on this engine and every other direct-injection engine, carbon cleaning is highly recommended. Some shops are doing this with a method called walnut blasting. Some use dry ice, some use special solutions that decompose the carbon. Either way works. The important thing is to do this regularly. More precisely every 60,000 miles or so.

You will have to pay for this service which costs between $300 and $600. But still, you will avoid some worse problems later on.

Honda 1.5 Engine Problems #2: Fouled Spark Plugs Because Of Carbon Buildup

We learned what is oil dilution and now let’s see what are the other problems. The last problem that we are going to cover is the spark plug fouling that often happens on these engines. The spark plugs on these engines can fail more often than on other engines.

This is mainly because this is a turbo engine. So, turbo engines along with direct injection are not making the life of the spark plugs easy. All of these engines often require replacing spark plugs much sooner than their naturally aspirated versions.

On this engine, you can expect to replace the spark plugs every 30,000 miles or so. Which is relatively soon. Considering that the spark plugs on naturally aspirated engines last for 100,000 miles in some cases.

When you have bad spark plugs (which you can confirm by knowing how to test spark plug and how to tell if spark plug is bad), you will start to feel some symptoms that will indicate this problem like rough idle, engine misfires (to find out more, check out our explainer on how to fix engine misfire), and loss of power.

What is good though is that the replacement of these spark plugs is cheap. There are 4 in total so, $50 in the worst case if you replace them by yourself. Nothing scary like the Honda oil dilution problem.

Honda 1.5 Engine Problems #3: Overheating and Cooling Issues

Overheating is another problem seen in Honda’s 1.5L engine. The turbocharger in the 1.5L engine generates a lot of heat. Although Honda has designed the cooling system to handle this, it sometimes fails under extreme conditions. This leads to overheating.

A faulty thermostat or a leak in the cooling system can exacerbate this problem. So, it is crucial to ensure the cooling system is in optimal condition. Regularly check for coolant leaks and ensure the radiator and thermostat are functioning correctly. If you experience overheating, stop the car immediately to prevent engine damage.

Honda 1.5 Engine Problems #4: Oil Leakage

Oil leakage is another issue that some owners have reported. The oil pan gasket and valve cover gasket are common places for oil leaks. If you see oil spots under your car, it’s crucial to get it checked out by a professional.

Oil leaks can lead to a low oil level which, in turn, can cause engine damage. Regularly check your oil level and ensure it is within the recommended range. If you find that you are frequently topping up your oil, it may indicate a leak.

Honda 1.5 Engine Problems #5: Turbocharger Failure

The 1.5L engine is a turbocharged engine, and while this provides better performance and fuel efficiency, it also introduces some potential problems. Turbocharger failure is one of them.

If you experience a sudden loss of power, hear a whining noise from the engine, or see excessive smoke from the exhaust, it might indicate a problem with the turbocharger. It is essential to address this issue immediately as a failing turbocharger can lead to severe engine damage.

Regular maintenance and using high-quality oil can help extend the life of the turbocharger.

Honda 1.5 Engine Problems #6: Fuel Injector Failure

The 1.5L engine uses high-pressure fuel injectors. These injectors can sometimes fail, leading to a variety of problems such as misfires, poor fuel economy, and a rough idle.

The fuel injectors need to be cleaned regularly to ensure they function correctly. If you experience any of the above symptoms, it is advisable to get the fuel injectors checked and cleaned or replaced if necessary.

Honda 1.5 Engine Problems #7: Transmission Issues

The CVT (Continuously Variable Transmission) used in Honda’s 1.5L engine can sometimes cause problems. Owners have reported issues such as shuddering, jerking, or a sudden loss of power.

The transmission fluid needs to be replaced regularly to ensure the CVT functions correctly. If you experience any of the above issues, it is advisable to get the CVT checked by a professional.

Tips for Maintaining Honda 1.5 Engine

While the Honda 1.5L engine has some common problems, proper maintenance can help extend its life and reduce the likelihood of issues. Here are some tips for maintaining your Honda 1.5L engine:

• Regular Oil Changes: Change the engine oil and filter every 5,000 to 7,500 miles. Use high-quality oil recommended by Honda.
• Check for Leaks: Regularly check for oil and coolant leaks. Address any leaks immediately to prevent further damage.
• Replace Spark Plugs: As mentioned earlier, replace the spark plugs every 30,000 miles or sooner if you experience any issues such as rough idle or misfires.
• Clean Intake Ports: Regularly clean the intake ports to prevent carbon buildup. This can be done by a professional using methods such as walnut blasting or dry ice cleaning.
• Maintain the Cooling System: Regularly check the coolant level and ensure the radiator and thermostat are functioning correctly.
• Check Turbocharger: Regularly check the turbocharger for any signs of wear or damage. Address any issues immediately to prevent further damage.
• Maintain Fuel Injectors: Regularly clean the fuel injectors to ensure they function correctly.
• Replace Transmission Fluid: Regularly replace the CVT transmission fluid to ensure the CVT functions correctly.

By following these maintenance tips, you can help extend the life of your Honda 1.5L engine and reduce the likelihood of experiencing any of the common problems mentioned above.

Honda 1.5L Turbo Engine Oil Dilution Lawsuit: Facts You Need to Know

1. Honda is facing a class action lawsuit from owners of 2018-2021 models, alleging that the “Earth Dreams” 1.5L turbo direct injection engine has a defect causing excessive oil dilution.
2. The defect causes fuel contamination of the engine oil, leading to engine wear and may result in catastrophic engine failure and stalling while driving.
3. Honda has allegedly failed to adequately repair vehicles affected by the engine defect, blaming owners for not driving their vehicles for longer distances.
4. The following vehicles are affected by this class action lawsuit: 2018-2021 Honda Accord, 2019-2021 Honda CR-V, and 2019-2021 Honda Civic.
5. The class action lawsuit is currently active and filed in the United States District Court for the District of Minnesota.
6. The problem has not been resolved with the MY2018-2021 Accords, 2019-2021 CR-Vs, or 2019-2021 Civics with the 1.5L turbo engine, despite various claims of software updates resolving oil dilution issues.
7. Honda recalled 350,000 CR-Vs in China for a similar issue in February 2022.
8. Symptoms of diluted oil include a check engine light, a gas-filled cabin that makes drivers nauseous and dizzy, and engine misfires (such as the Dodge P0300 code).
9. To identify if your car has a turbo 1.5-liter Earth Dreams engine, check the model and trim level (to find out more, check out our write-up on what does SE mean on a car).
10. Affected owners can submit their Honda car complaint to join the class action lawsuit and be notified of important case details.

Honda Oil Dilution: In Conclusion…

In this article, we have covered quite a bit when it comes to the Honda oil dilution problem. In the beginning, we focused on the 1.5 engine since this is the engine that is most affected by this problem. Then we learned more about its specs and the applications in which this engine is included.

Then we covered the problems of this engine with the main focus on the oil dilution issue and how big of a deal this problem is. We learned that Honda has issued an extended warranty for cars produced between 2016 and 2018. So, if your vehicle is eligible, you can take it to a Honda dealership. Lastly, we covered the other problems that this engine has.

Honda Oil Dilution: Frequently Asked Questions (FAQs)

Here are some popular frequently asked questions (and their answers) for the Honda oil dilution problem…

Who Makes Honda Oil

Honda engine oil is made by various manufacturers and may vary by region. Honda works with several oil companies to produce oil that meets their specific requirements and standards. For example, in the past, Honda has partnered with companies like Mobil to produce oil specifically designed for Honda engines. It is always recommended to use oil that meets Honda’s specifications to ensure optimal performance and longevity of the engine.

Did Honda Fix the Oil Dilution Problem for 2023

As of writing, Honda has made efforts to address the oil dilution issue in their 1.5-liter engines by implementing some design changes and software updates. These changes were made to reduce the chances of fuel mixing with the oil, a problem that was particularly prevalent in colder climates. However, it is advisable to check with a Honda dealership or consult the owner’s manual for the specific model year in question to confirm if the issue has been completely resolved.

What Causes Fuel to Mix with Oil

Fuel can mix with oil due to several reasons. One common cause is short trips in cold weather, where the engine does not reach its optimal operating temperature. This can lead to incomplete combustion of fuel, causing some fuel to pass through the cylinder walls and mix with the engine oil. Other causes can include faulty fuel injectors, which can leak fuel into the engine, and worn piston rings, which can allow fuel and combustion gases to enter the crankcase.

Which Is Better Civic or Accord

Both the Honda Civic and Honda Accord are reliable and popular vehicles, but the best choice depends on your needs and preferences. The Civic is a compact car, while the Accord is a midsize sedan. Generally, the Accord offers more space, a more comfortable ride, and more features, but it also comes with a higher price tag. The Civic, on the other hand, is more affordable, offers good fuel efficiency, and is easier to maneuver in tight spaces. It ultimately depends on what you value more in a vehicle.

Did Honda Fix the Oil Dilution Problem

Honda has taken steps to address the oil dilution issue in their 1.5-liter engines. They have made some design changes and software updates to reduce the chances of fuel mixing with the oil. These changes were made in response to complaints from owners and have been implemented in newer models. However, it is always advisable to consult the owner’s manual or check with a Honda dealership to confirm if the issue has been completely resolved for a specific model year.

What Problems Do Honda CR-V Have

The Honda CR-V has had various problems over the years, but one common issue has been the oil dilution problem in the 1.5-liter turbocharged engine. This problem causes fuel to mix with the engine oil, leading to increased oil levels and the potential for engine damage. Other reported problems include issues with the infotainment system, problems with the electrical system, and transmission issues. However, it is worth noting that the CR-V is generally considered to be a reliable vehicle, and these issues do not affect all models.

How to Fix Oil Dilution

Fixing oil dilution may require a combination of actions. First, it is important to change the engine oil and filter at the recommended intervals or sooner if you suspect oil dilution. Driving the vehicle for longer distances and allowing the engine to reach its optimal operating temperature can also help reduce oil dilution. Additionally, Honda has made some design changes and software updates to address this issue, so it may be helpful to check with a Honda dealership to see if any updates or recalls are available for your vehicle.

Is the Honda 1.5 L Turbo Engine Reliable

The Honda 1.5-liter turbo engine has faced some reliability concerns, mainly due to the oil dilution issue. This problem, which causes fuel to mix with the engine oil, has raised concerns about the long-term reliability of the engine. However, Honda has taken steps to address this issue by implementing design changes and software updates. Apart from this issue, the 1.5-liter turbo engine is generally considered to be reliable, but it is always advisable to perform regular maintenance and check for any recalls or updates that may apply to your vehicle.

Are Honda Turbo Engines Reliable

Honda turbo engines are generally considered to be reliable. However, there have been some concerns about the 1.5-liter turbo engine due to the oil dilution issue. This problem causes fuel to mix with the engine oil, which can lead to increased oil levels and the potential for engine damage. Honda has made efforts to address this issue by implementing design changes and software updates. It is always recommended to perform regular maintenance and check for any recalls or updates that may apply to your vehicle.

How to Prevent Oil Dilution

Preventing oil dilution may involve a few different strategies. Firstly, try to avoid making too many short trips in cold weather, as this can lead to incomplete combustion of fuel and increase the chances of fuel mixing with the oil. Regularly changing the engine oil and filter at the recommended intervals can also help reduce the risk of oil dilution. Additionally, driving the vehicle for longer distances and allowing the engine to reach its optimal operating temperature can help reduce the chances of oil dilution. Lastly, check with a Honda dealership to see if there are any software updates or recalls available for your vehicle that may help address this issue.

Do Hondas Burn Oil

Some older Honda models have been reported to burn oil, which can be caused by factors such as worn piston rings, a faulty PCV valve, or infrequent oil changes. However, newer models are less likely to experience this issue, as Honda has made design improvements to address it. It is always advisable to perform regular maintenance, including changing the engine oil and filter at the recommended intervals, to help prevent oil burning and other engine problems.

Which Hondas Have the Earth Dreams Engine

The Earth Dreams engine is a range of engines developed by Honda to achieve higher fuel efficiency and lower emissions. These engines are used in various Honda models, including the Honda Accord, Honda CR-V, Honda Civic, and Honda Fit. The Earth Dreams technology includes a range of features such as direct fuel injection, variable valve timing, and turbocharging to achieve better performance and fuel efficiency.

Why Do Hondas Burn Oil

Hondas, like any other vehicle, may burn oil due to several reasons. Worn piston rings, a faulty PCV valve, or infrequent oil changes can all contribute to oil burning. In the past, some Honda models were reported to burn oil more frequently than others, but Honda has made design changes and improvements to address this issue in newer models. Regular maintenance, including changing the engine oil and filter at the recommended intervals, can help prevent oil burning and other engine problems.