What are the symptoms of a bad engine crankshaft?
3 Answers
There are many symptoms of a bad engine crankshaft. Here is a detailed introduction to engine crankshaft damage: 1. Specific symptoms: When the crankshaft is damaged, the crankshaft clamp will loosen and swing up and down. In severe cases, the engine may be directly scrapped. There will be no high-voltage electricity, no fuel injection, failure to start the car, and the engine fault light on the dashboard will illuminate. 2. The role of the crankshaft and engine: It bears the force transmitted by the connecting rod and converts it into torque, which is then output through the crankshaft to drive other accessories on the engine. The crankshaft is subjected to the combined effects of centrifugal force from rotating masses, periodically changing gas inertial forces, and reciprocating inertial forces, causing it to bear bending and torsional loads. The engine converts the thermal energy of gasoline or diesel into mechanical energy by burning the fuel in a sealed cylinder, causing the gas to expand and push the piston to perform work.
Having driven for over twenty years, the symptoms of a failing engine crankshaft are quite noticeable. The most common sign is a rattling noise under the hood, like small hammers tapping on metal, especially loud during startup. Sometimes you can feel the entire car vibrating, with the steering wheel shaking violently, and pressing the accelerator doesn’t provide much power—it’s as if the force is being swallowed. Additionally, the sudden illumination of the engine warning light is another red flag. I’ve experienced it myself once, and thankfully, I got it checked in time; otherwise, the car might have completely broken down on the road. A damaged crankshaft is no small issue—it connects to the pistons and other components, and once it fails, the consequences range from troublesome repairs to complete engine failure. My advice is not to delay if you hear strange noises or notice abnormal vibrations; take it to a reliable repair shop right away. Don’t wait until the car won’t move to regret it.
When I first started learning car repair, I was curious about how to identify engine crankshaft issues. After observation, I found there are quite a few symptoms. For example, when starting the engine, there would be continuous low-pitched knocking sounds, and when sitting in the car, the vibration under the seat is particularly strong, becoming more noticeable at high speeds with a buzzing sensation. Another aspect is performance changes, such as unstable engine RPM or sluggish acceleration. I once encountered a customer's car that always felt like there was resistance when accelerating. It's also important to check the oil condition—if there's oil leakage or the oil pump warning light comes on, it might be related to crankshaft failure. When I used tools to test, I found that abnormal noises were easily amplified, making diagnosis not too difficult. Addressing such issues promptly can prevent a chain reaction; otherwise, repair costs could skyrocket.
