Why does the car feel sluggish after carbon deposit cleaning?

[VanElliott]

It may be due to damaged valve stem seals. Symptoms of aging or damaged valve stem seals: 1. The engine burns oil, emitting blue smoke. 2. Severe carbon deposits on spark plugs, leading to reduced engine power. 3. Decreased sealing performance results in insufficient cylinder pressure, causing reduced engine power. 4. Accelerated oil consumption, and in severe cases, it can directly cause engine seizure due to lubrication and cooling failure. Reasons for oil seal aging and oil leakage: 1. Assembly issues: During assembly, if the threads or splines are not aligned properly, the misaligned parts will leak oil due to poor sealing, and the oil seal itself may also be damaged. 2. Material problems: If the spring tension does not meet the technical requirements, excessive tension can cause improper fit between the oil seal and the rotating shaft, leading to abnormal wear. Conversely, insufficient tension results in inadequate pressure to seal properly. 3. Misalignment between the oil seal and the rotating shaft: This causes uneven wear, leading to abnormal wear on the sealing lip. 4. Lack of lubricant on the sealing lip: This results in dry friction, and mechanical wear will quickly flatten the sealing edge.