Learning that there is oil on your spark plug can be quite daunting because it means that you might encounter some challenges in the smooth running of your car. Before you panic, know that the issue might not be as bad as it sounds.
Many factors can be responsible for oil on spark plug. Some of them can be as a result of spark plug o-ring or because the valve cover is leaking. And if that is the case, then they can be replaced easily. However, there are times the issue is more serious, especially if it is from a leaking head gasket.
Oil is important in your car engine, but there are places it shouldn’t get to. So, if you notice that there is oil in your spark plug, you need to pay attention to it before it escalates.
What Is The Function Of A Spark Plug?
In case you didn’t know before now, spark plugs play a very vital role in your ignition system. The spark plugs are the reason your ignition picks up. The reason your car combustion chamber maintains the right temperature is a result of the spark plugs.
The combustion procedure is quite delicate, which is why a lot of things can affect how it works. A lot of power can be lost if the temperature of the combustion chamber is low, leading to low energy. If the temperature is very high, it can lead to what is called pre-ignition.
This is why every vehicle manufacturer checks the right heat range for each vehicle without generalizing all with the same range. Therefore, it’s important you know this so that you don’t go with other heat range that isn’t meant for your car.
What Having Oil On Spark Plug Does To Your Engine?
When there is oil on your car spark plug, it makes it difficult for there to be a spark, which means no combustion and ignition. Even if the fuel pump is pumping the right fuel, it will find a way to escape the cylinder without burning.
We have already stated that when your spark plug is soaked in oil, it affects the temperature of the combustion chamber and will affect the way the engine performs. The worst thing that can happen when your spark plugs are soaked with oil for a long time is that it can destroy the catalytic converter. It can also wear out the engine bearings because of too much gasoline that piles up in the oil pan.
Why Is There Oil On My Spark Plugs?
With the way the combustion system is wired, it is only the fuel and air mixture that should touch your spark plugs. There is no provision for oil to be on your spark plug. But there are some reasons why oil gets to your plugs. Here are 6 of them:
1. Leaking or worn valve guides
The role of the valve guides is to regulate the way the combustion chamber takes in air. The valves are always there to maintain the right position as the engine is on and running. Therefore, when these guides start leaking or are worn out, it predisposes the spark plugs to oil since it makes it easy for oil to leak.
In most modern cars, you will find the spark plugs somewhere around the exhaust and intake valves. Therefore, it is possible to witness oil on spark plug since they are close to the valves due to the oil leakage.
2. Broken piston
A cracked or broken piston can be the reason your spark plugs have oil on them. This is a common occurrence when the piston heats up. And this is because the engine is in operation, and the heat generated is too much leading to cracks.
Such cracks pave the way for the oils to find their way to the combustion chamber and unavoidably to the spark plugs. There are easy ways to tell if the piston is broken, which are, rattling noise, noticeable power loss, and engine misfire as the car is running.
When unattended, such a broken pistol can cause lasting damage to your vehicle. The more time you delay in replacing it, the more money you will spend in trying to resolve the issue.
3. Leaking O-ring seal
These are located somewhere in the lower part of the spark plug well. Their function is to ensure that oil does not get to the spark plugs. Therefore, when this part is faulty or no longer working, it creates a way for oil to pass through the valves and leak into the spark plugs. When this happens, you will start noticing that the engine is misfiring. And this must be attended to avoid leading to more expensive engine issues promptly.
As a car owner, you should endeavor to check to make sure that the seals are still intact to prevent such occurrence.
4. Faulty piston compression rings
When the piston compression rings are damaged, it will also lead to oil settling on your spark plugs. The compression rings are located at the higher and lower part of the engine so that oil will not leak from the engine oil and into the combustion area.
The compression also rings clear excess oil that gets to the cylinder walls so that there are none left to get to the combustion chamber. So, in a situation where these rings are no longer in good working condition, the oil will surely find its way through the piston and then to the combustion chamber and inadvertently on the spark plugs as well.
5. Leaking valve cover gasket
The spark plugs are not the only thing that is located on the head of the cylinder. The valve cover gasket can also be found there. And their work is to contain the engine oil and make sure it doesn’t get pass the cylinder head. If this is working well, oil cannot get to the spark plugs.
But because the temperature in the engine is often high, it causes easy wearing out of the valve cover gasket and ultimately to its final damage. You can already tell what will happen when this part is no longer functioning properly.
6. Blown head gasket
Some people overlook a head gasket that is blown and often regard it as a minor issue. But this is another reason oil gets into the spark plug. Apart from that, it may lead to more serious engine issues. The head gasket is part of the things that can be found on the combustion chamber at the top where it seals the cylinder head. It goes without argument that oil on spark plug will be the result when it is blown.
People have had to spend a massive sum of money trying to fix issues arising from a bad head gasket. So, the earlier you identify the problem, the cheaper it will cost to fix it.
How To Tell If There Is Oil On Spark Plug
We have pointed out the things that could cause the oil to get to the spark plug. However, you still need to know the signs and symptoms that your spark plug has oil on it. Discovering it on time will save you some money and make for easier fixing. Here are the symptoms:
a. Reduced engine performance
Once you notice that your engine no longer serves you as it ought to, then it is a sign that something is wrong. Since the spark plugs are part of the components in the engine that ensures its smooth operation, when they have oil them, this will affect the performance and also the hesitancy.
b. Gas smell emanating from the exhaust pipe
This is when there is a mixture of oil and gas that comes from the tailpipe, which is also followed by a particular gas smell. Most times, you will be able to perceive this smell from your car cabinet.
c. Misfiring engine
Once there is no more combustion happening in the cylinder, the engine will misfire. Although there are other reasons this could happen, oil on the spark plug is usually one of the causes. So, it will be beneficial if you can check to find out what is causing the engine to misfire.
d. Exhaust pipe emitting blue smoke
Whenever you notice that your exhaust pipe is bringing out blue smoke, the simple explanation is that the engine is burning oil somewhere. This usually happens when there is oil in the spark plugs. It is as a result of the burning of the fuel, air and leaked oil on the tips of the plugs that the smoke is escaping from the exhaust.
e. Engine backfiring
In case you are wondering if there is such thing as engine backfiring apart from misfiring as we have mentioned, then the answer is yes. When there is oil on the spark plugs, the engine will backfire. What this means is that fuel particles aren’t properly com-busted as they should and finds it way to the exhaust with force. That is why you hear the sound of small explosions from the engine.
f. High fuel consumption
Oil on your spark plugs can affect their efficiency and cause your car to be using up more fuel than is usual. Therefore, whenever you notice high fuel consumption, make sure to check it out and find the root cause.
How To Solve The Issue Of Oil On Spark Plug
The following process will help you fix the issue you are having with oil on spark plug regardless of whether you are a new or old driver.
1. Turn off the engine
You need first to turn off your car and then proceed to disconnect your car battery terminals. This will ensure that the engine is off and not supplying power.
2. Take out the valve covers
The next step is to remove the valve cover. To do this, get a screwdriver so that you can easily open it. Once you have done that, you will be able to see the spark plugs and the tunes. The seals and gaskets will also be exposed and will give you a clear view of the things that are faulty and need to be worked on or replaced entirely.
3. Clean the valve and head cover
There is a need for you to clean the head and valve cover before installing new gaskets and seals. Endeavoring to clean these parts helps in removing old particles and for the new parts you are installing to have a tight seal. When cleaning, only use plastic equipment so that the cylinder head or valve cover does not get damaged in the process. While at it, make sure you are using the right greaser alongside.
4. Fix new gasket and O-ring seal
Now that you are done with the steps listed above, it’s time to install a new O-ring seal and gasket. Some engine requires that you apply a recommended silicone while at it.
5. Fix new spark plugs
We have come to the final step, which is to remove the old spark plugs and replace them with new ones. Don’t be tempted to clean and use the old plugs again, as this may still have some oil contained within. Since the spark plugs are already faulty, the best thing is to replace them with new sets.
While oils on spark plug can give you some scare, the good news is that it doesn’t warrant a total change of the car engine. Try and develop the habit of observing some symptoms from your car that were not there before. This will help you nip the problem in the bud and not allow it escalate into harder problems.
Ensure that you always replace all the parts that need changing from time to time. Have a car maintenance routine you follow, and you won’t have to worry about having issues with your car engine.
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