Oil is the life source of any internal combustion engine, and running low on engine oil can result in catastrophic engine failure, so what are the low engine oil symptoms?
Chronologically, the symptoms are:
- Engine oil light
- Burning oil smell
- Engine knocking
- Engine overheating
- Worsening performance
- Complete engine failure
Now that you know the symptoms let’s go more in-depth on what causes these low engine oil symptoms.
6 Low Engine Oil Symptoms
1. Engine Oil Light
The engine of all modern vehicles has an oil level sensor, either a float switch or conductive style sensor, that will turn on the engine oil light if the oil goes under a certain level.
When the engine oil light turns on, it is best to safely get off the road as quickly as possible to eliminate any chances of engine damage.
Get the vehicle towed, then risk driving any further or get someone to get you engine oil to top up the car or take you to get oil.
2. Burning Oil Smell
If you ignore the oil light or, for some reason, the light doesn’t come on, you will start smelling oil burning.
This happens because the oil is too low for the oil pump to pick up, and all the rotating components, including the oil pump, are running dry.
Since the rotating assembly of the vehicle is just metal on metal contact surfaces, without oil, they start getting hot and burn away any oil that is still trapped between the bearing surfaces resulting in the burning oil smell.
3. Engine Knocking
It won’t take long after the burning oil smell to hearing the engine start knocking, and the longer you drive, the louder the knocking sound will become.
Since the bearing surfaces inside the engine on the rotating assembly have run dry, and t is now running metal on metal, the temperatures on these contact points will get metal scorching hot.
It will get so hot that it will eat away at the bearing surfaces until the bearings fail and start disintegrating, resulting in the free play of the components.
Free play on the rotating assembly results in a knocking sound you will hear.
At this point, the engine will need to be rebuilt.
4. Engine Overheating
As we established with the bearing surfaces dry and running metal on metal, this generates a lot of heat, more heat than the engine cooling system was designed to cope with.
The water temperature gauge will start going up and pin itself to the max temperature line.
This extreme overheating situation can result in the cylinder head gasket failing.
The engine is now in such a state that it won’t make any sense to repair it but replace it.
5. Worsening Performance
With one or many of the bearings gone, the amount of internal engine friction will result in the car performing worse the longer it runs in this state.
It will worsen to such a point where the vehicle will barely move even at full throttle, and then the end is close.
Here is an informative video on how the engine performance degrades from MasterMilo on Youtube trying to keep a Renault Clio running as long as possible without any oil:
6. Complete Engine Failure
The engine will run poorly up to a point and stops entirely and, in many cases, very violently.
If the vehicle is moving while this happens, the engine can lock up the entire drivetrain, resulting in a spin-out or crash.
At this point, the rotating assembly and bearing surfaces have seized together, and sometimes even friction welded themselves together.
Final Thoughts On Low Engine Oil Symptoms
With low engine oil, you just need to act quickly and safely to ensure that you do not damage the engine and keep an eye out for the engine oil light or burning oil smell.
The last thing you want to replace an engine because it is very costly, so before a long trip, check the level of the oil and try to keep the engine oil at the correct quantity.
Hopefully, you found this article helpful in recognizing the symptoms of an engine with low engine oil.
What Does An Engine with Low Oil Sound Like?
At first, it won’t sound any different than an engine with oil, but the longer the engine runs, it will develop a knocking sound.
This is because the bearings inside the motor must wear down until it develops free play in the rotating assembly before making the knocking sound.
Will A Car Shake If Low On Oil?
No, the engine will function as normal until it has no more oil or insufficient quantity to reach the oil pump, but even then, it will take minutes for the engine to start knocking and eventually start shaking.
The oil light will come on before the car starts shaking because the engine is worn out.
Can I Start My Car After Adding Oil?
Yes, as long as the sump plug is securely fastened, the oil filler cap is closed, and you have the correct quantity of oil on the dipstick, you can start your car.
Also, make sure you have the correct manufacturer-specified oil for your vehicle.