What are the symptoms of a bent engine connecting rod?
2 Answers
If the engine connecting rod is slightly bent or deformed, it may result in the engine failing to start. After starting, the engine may exhibit unstable idling, severe shaking, and accompanied by knocking sounds. Additionally, professional tools are required for measurement, which needs to be conducted at a repair shop. Extended Information: The following are the causes of a bent engine connecting rod in a car: 1. Water entering the engine cylinder: As the amount of water increases, it accumulates on top of the piston, reducing the effective volume of the combustion chamber, increasing compression resistance, and consequently increasing the pressure transmitted from the piston to the connecting rod. 2. Abnormal engine fuel injection system: This situation is usually caused by continuous fuel injection from one of the engine's injectors. Symptoms often include difficulty starting, unstable idling, black smoke from the exhaust pipe, and reduced power. 3. Connecting rod seizing with the crankshaft: This is generally caused by poor engine lubrication and can be determined by checking the wear condition of internal engine components. 4. Issues with the connecting rod itself: This can usually be confirmed through methods such as chemical composition analysis of the connecting rod material, hardness testing, metallographic examination, and scanning electron microscope fracture analysis.
If the engine connecting rod is bent, you'll definitely notice something wrong while driving. I've encountered similar cases when I used to repair cars frequently. The key signal is abnormal knocking noises, especially a thumping sound during acceleration or uphill driving, like metal hitting metal. Engine vibration also increases significantly, with the steering wheel or the entire car body shaking violently. In terms of performance, you'll feel a lack of acceleration power—no matter how hard you press the gas pedal, it feels like a snail crawling, with a noticeable drop in power output. Sometimes it's even difficult to start the engine, or it suddenly stalls while running, all because the bent connecting rod affects piston movement. If you see blue smoke or an abnormal increase in engine oil level, it's even more dangerous, as the cylinder wall might be damaged. I recommend stopping immediately for inspection—don't push through and keep driving, or the engine might be ruined. Regular maintenance and oil changes can prevent this issue, as can avoiding water ingress or overloading accidents that cause bending.
