What happens when engine oil reaches the upper limit?

[SanKathryn]

The effects of engine oil reaching the upper limit are as follows: 1. Increased resistance and reduced power: It increases the rotational resistance of the crankshaft, reducing the engine's output power. 2. Increased fuel consumption: Excess oil can enter the combustion chamber and participate in combustion, causing the vehicle to burn oil, emit blue smoke, and consequently increase fuel consumption. 3. Increased carbon deposits: The residue from burned oil accumulates on the walls of the combustion chamber, reducing the space in the combustion chamber, thereby lowering the engine's compression ratio. It also accelerates wear on the cylinders and pistons, reducing the vehicle's lifespan. Note: When adding engine oil, it is advisable to keep the level slightly below the mark on the dipstick.