Is your car losing oil but no leak or smoke? Your vehicle’s engine requires oil to operate normally. It consumes an average of a quart for 2000 miles. However, if your vehicle is burning oil faster, it could be because the engine has internal damages.
So, when you notice the engine is consuming oil faster, ensure you act immediately to avoid incurring costs to fix the damages. Sometimes, your car might start losing oil without any leak or smoke which might leave you confused.
Is your car losing oil, and there is no smoke or leak?
The reason could be a faulty PCV valve, which might prevent natural oil flow in the engine. At the same time, extra pressure makes fuel degrade the car’s cylinders.
Therefore, if your car is losing oil with no smoke or leaks, it consumes more fuel, and you will have to fuel it more than its normal demands.
Do you want to learn more?
Continue reading this article, and you will get all your answers on the issue of the car losing oil with no smoke or leak.
Car Losing Oil but No Leak or Smoke Causes
It is not uncommon for your automobile to start consuming more oil as it gets older. While it is not rare, if your car is consuming too much oil, then you should be concerned.
Here are some reasons why your vehicle is losing oil with no smoke or leaks and their solutions;
1. Oil Leaks
If you do not see any leak or smoke, but your car is consuming much oil, then the oil could be leaking internally in the car and can be quite small to notice.
Alternatively, your vehicle could be leaking the oil via tiny cracks because the pipes are worn out. It means that the leaking will not leave behind any huge puddle of oil underneath your automobile, so still, you will not experience any weird-smelling of smoke.
Most leaks are caused by worn-out engine gaskets, faulty connections, oil seals, and oil pan leaks.
So, if you are not sure where your car is losing oil, and you are not noticing any leaks, crawl beneath your vehicle and inspect your oil pan seal and draining plug of the oil pan. After that, inspect the valve cover gaskets and timing cover seals to see any signs of oil leaks.
Here are the signs of oil leaks you should expect as you inspect the above elements underneath your car;
- Dark yellow or brown puddles under the vehicle
- The illuminating dashboard light
- The engine releasing some smoke
- Burning oil smell
- Overheating engine
At the same time, if you want to be sure if the oil leak is not responsible for your vehicle to lose too much oil, visit an expert or professional mechanic. They will be in a better position since they have tools to help inspect tiny cracks in the car’s system.
2. Faulty Piston Rings
In the steam engine or the internal combustion engine is a metallic ring connected to the pistons outside diameter called a piston ring.
Here are the major functions of the piston rings;
- To seal the combustion chamber and ensure the least loss of gases to the crankcase.
- Regulate consumption of engine oil usage by removing the motor oil from the cylinder and returning it to the sump.
- Improves transfer of heat from the piston to the cylinder wall
- Maintains perfect oil quantity between the cylinder wall and the piston
The major causes of wearing out of piston rings are dirt and contaminated engine components. Dirty air filters can also cause the failure of engine fuel.
Therefore, if you realize your car is consuming a lot of oil, there is white exhaust smoke, the car is accelerating poorly, or the engine is performing poorly in general, the pistons are worn out.
3. Damaged PCV Valve
PCV (Positive Crankcase Ventilation) is the crankcase that helps to hold the car’s motor oil and is positioned at the engine’s bottom.
When your car burns fuel in the engine, it releases waste gases emitted via the exhaust system. However, some gases pass past pistons and enter the crankcase.
In the crankcase, the gases and oil mix produce oil sludge which might damage some engine components by corrosion or even clog the engine passages.
Waste gases cannot enter the engine via the crankcase but can only exit through it.
Therefore, if the PSV is clogged, it may increase oil consumption since pressure is likely to build up if vapors in the crankcase do not flow in the combustion. The pressure leads to oil passing through the seals and gaskets.
4. Faulty Head Gasket
It helps seal the cylinder’s combustion gases, hence avoiding any coolant or engine oil leakages in the cylinder.
So, if the gasket head has holes or any cracks, it starts to fail and leads to loss of compression on one side of the seal. The issue causes gases to escape and leak in the car’s engine oil and eventually causes the oil to break down with time.
If the gasket leaks, it leads to overheating, and the engine starts running poorly.
Therefore, your car can start losing oil without any smoke or leak if the gasket is faulty and only functions as a sponge. Thus the gasket starts absorbing fluids because of the much surface tension and then releases the oils if they lack adequate tension.
5. Dirty Oil
Having oil to run your car is not enough; sometimes, the oil degrades, so it is important to change the oil once in a while. You can also ensure you change your oil filter since if the oil filter is not working properly, your car oil will likely get dirty or contaminated.
It is important to note that dirty oil is even more damaging than your car lacking oil.
Therefore, if your motor oil loses its thickness or viscosity, it will likely be invaded with metals, dirt, and more debris. This dirt and debris makes your motor oil actively corrosive and increases the wearing out of engine components.
The first effect you will experience with dirty oil is the poor fuel economy of your car.
Simultaneously, your car will start losing oil because of dirty oil but no smoke or leaks. Also, the dirt gets in the engine coating beneath the motor walls and other components, leading to wearing out such parts.
Therefore, dirty oils lead to wearing out of some engine components, which can cause your cause to lose oil with no leaks or smoke.
6. Damaged Valve Seal
The cylinder heads are small gaskets that hold the valve stems and seal them. Also, the seals help to stop lubricants from getting in the cylinder. They are essential parts that help maintain the compression level of your car’s engine.
Valve seals help regulate the valve lubrication and regulate oil consumption, so if it is broken, there will be no regulation of oil consumption and lubrication.
Therefore, faulty or worn-out valve seal leaks oil into the car’s engine cylinder and the combustion chamber eventually.
7. Faulty Cylinder Walls
Pistons travel via the cylinder walls by the energy produced by air and fuel mixture in the combustion chamber.
The crankshaft rotates, and from the oil pan, it pulls oil and moves the oil to the cylinder walls to lubricate it. Since the valves are closed, carbon deposits might break off and affect the cylinder walls adversely in the process of combustion.
Other causes of damaged cylinder walls are;
- Uneven over-tightening of cylinder head causing it to distort
- Distorted threads or dirt on head bolts of the cylinder
- Lack of enough lubrication on contact areas of the bolt head
- Uneven seal on the cylinder head
Thus, if the cylinder wall has a fault or is damaged, the piston rings will allow motor oil to enter the combustion chamber, causing it to burn and consume your oil, meaning you have less oil.
On Car Losing Oil but No Leak or Smoke
For optimum operation of your car’s engine, car oil is vital. When you notice your car consuming too much oil than normal, you might get concerned.
While cars often consume more oil as they get older, you should check out the problem if you notice the oil consumption is too much and there is no smoke or leak.
As discussed in this article, the causes for losing oil with no leaks or smoke include dirty oil, faulty head gasket, oil leaks, damaged PCV valve, faulty pistons, damaged cylinder walls, and damaged valve seal.
If the problem results from dirty oil, ensure you change the oil and the oil filters too. Changing oil often and ensuring the oil filters are clean will protect your engine and save you a lot of trouble.
However, if your car is losing oil with no leaks and you don’t seem to find the problem after inspecting it, it would be best to call an expert mechanic to check the exact cause and fix it immediately.
Hi I’m Marshall based in 1478 Doctors Drive Santa Monica, CA. I’m your DIY Car Repairman with more than 5 years experience in automobile repair, a skill I learned from my old man.
I started this blog to share my experience on both simple and technical aspects of your car.