A bent crankshaft can lead to which issue?

A bent crankshaft can significantly impact engine performance, particularly affecting the compression levels within the cylinders. When a crankshaft is bent, it alters the alignment and timing of the engine's moving parts, which can cause the piston to sit improperly in the cylinder. This misalignment typically leads to low compression rather than high compression or any issues related to loose fasteners or excessive fuel consumption.

Low compression occurs because the piston's ability to properly seal against the cylinder walls is compromised, allowing air-fuel mixture to escape. This results in a decrease in engine efficiency, performance, and power output. While a bent crankshaft might cause various performance issues, its most direct impact is on the compression ratios of the engine, emphasizing the importance of maintaining proper crankshaft integrity for optimal functioning.