What are the effects of overfilling engine oil in a sedan?

[VanIsabela]

The effects of overfilling engine oil in a sedan: 1. Excess oil can easily enter the combustion chamber (due to excessive internal pressure) and produce gummy carbon deposits; 2. The excess oil will reduce the gas volume in the crankcase to some extent, leading to increased pressure, which can easily damage the engine's sealing (oil leakage). Taking the example of excess oil easily entering the combustion chamber (due to excessive internal pressure) and producing gummy carbon deposits, although no obvious effects may be noticed initially, over time, the carbon deposits will become increasingly severe, potentially clogging the three-way catalytic converter pores and causing excessive exhaust emissions.