You’ve changed your car’s engine oil yet again. Everything seems to be fine, but after a while you decided to check its level and suddenly you smelled a strange smell. Should I immediately panic? And if so, in which case?


  • a What should engine oil smell like?
  • 2 How to identify the problem by the smell of oil
    • 2.1 The burning smell
    • 2.2 Strong chemical smell
    • 2.3 Smell of burnt matches
    • 2.4 The smell of gasoline

What should engine oil smell like?

New, high-quality engine oil should be transparent, have a golden color and have a sweet, unspoken smell. Some brands of original oils do not smell at all, while counterfeits have a strong chemical “flavor”. This means that they could be made from poorly refined materials or already used with the addition of incomprehensible additives of unknown action. It is better not to pour such a substance into the engine of your car.

Fearing counterfeits, some manufacturers specifically produce engine oil with a recognizable, but not overpowering and even pleasant smell. Of course, during engine operation, this changes. But when the lubricant begins to smell noticeably of acid or, God forbid, rotten eggs, it means that it has exhausted its resources and needs to be replaced urgently.

How to identify the problem by the smell of oil

Modern lubricants provide uninterrupted operation of the engine with a mileage of more than 10,000 km. Although some motorists, referring to the poor quality of gasoline, try to change the lubricant more often. After about 5-6 thousand km. If bad changes occurred with the oil earlier, they may indicate problems with the engine and its systems.

The burning smell

Easily eliminated causes of the burning smell of engine lubricants can be: aggressive driving style and poor quality of oil or antifreeze purchased. In this case, you should take better care of your car and replace lubricants and coolants.

However, it is possible that the lubricant “burns” due to a malfunction in the engine cooling system. Then this problem can only be solved in a car service after a profile diagnosis.

Strong chemical smell

If the engine oil has a strong chemical smell, the reason for this may at best be its poor quality. And you will need to urgently replace the engine lubricant by purchasing a product from a trusted manufacturer.

Another, more serious reason for the appearance of chemical “amber” may be the ingress of antifreeze into the engine lubricant.

This can happen after:

  • head gasket damage;
  • violation of the integrity of the cylinder block housing;
  • improper fluid pump installation.

To solve these problems, you will have to turn to specialists.

Smell of burnt matches

The appearance of a sulfuric smell indicates that such an amount of exhaust gas has entered the combustion chamber that oil additives cannot cope with the neutralization of sulfur compounds. If the engine lubricant is of high quality, the problem is most likely due to the destruction or deformation of the valve cover gasket. The problem must be resolved immediately, otherwise the engine systems could be damaged.

The smell of gasoline

Gasoline ingress into engine lubricants is a very serious problem. This can result from:

  • poor performance of engine injectors;
  • deterioration of the piston group;
  • vacuum fuel regulator malfunctions;
  • ignition system malfunctions.
In such a situation, the car needs serious repairs and should be delivered to car service professionals as soon as possible.

Although there is a small chance that gasoline gasoline in oil appeared due to the use of low-quality fuel.

Of course, the first thought after smelling a strange smell coming from engine oil is to change it. And maybe changing all the lubricants, coolants and fuels will improve the situation. However, if the cause is some kind of serious breakdown, then while you are experimenting, the condition of the car’s systems can deteriorate significantly. Therefore, it is better to clear up any doubts in a car service. It may be more expensive, but it’s more reliable and safer.