It is normal for some engine oil to be consumed during normal engine operation. The following are reasons for oil consumption during normal engine operation.
The oil is used to lubricate pistons, piston rings and cylinders. A thin film of oil remains on the cylinder wall as the piston moves down the cylinder. The high negative pressure generated during vehicle deceleration draws some of this oil into the combustion chamber. This oil, as well as some of the oil film remaining on the cylinder wall, burns out due to the high temperature of the exhaust gases during the combustion process.
Oil is also used to lubricate intake valve stems. Some of this oil is sucked into the combustion chamber along with the intake air and burned along with the fuel. The high temperature of the exhaust gases also burns the oil used to lubricate the exhaust valve stems.
The amount of engine oil consumed depends on the viscosity of the oil, the quality of the oil and the driving conditions.
When driving at high speeds and frequent acceleration and deceleration, more oil is consumed.
A new engine consumes more oil because its pistons, piston rings and cylinder walls have not yet worn in.
Note. Oil consumption: max. 1.0 l per 1000 km.
When estimating the amount of oil consumption, keep in mind that the oil can be diluted and it will be difficult to accurately estimate its true level.
For example, if the car is used for frequent short trips and consumes a normal amount of oil, the dipstick may not show any drop in oil level even after driving 1000 km or more. This is due to the fact that the oil is gradually diluted with fuel or moisture, giving the appearance that the oil level has not changed.
The diluting ingredients evaporate when the vehicle is driven at high speed, such as on a motorway, resulting in excessive oil consumption after driving at high speeds.
One of the most important points in proper vehicle maintenance is keeping the engine oil at the optimum level so that the performance of the engine oil does not deteriorate. Therefore, it is very important to check the oil level regularly. Toyota recommends checking the oil level every time you fill up your vehicle with fuel.