Can the Engine Start with a Bent Connecting Rod?

[AuroraAnn]

If the connecting rod is slightly deformed, it will not completely affect the engine's operation, but the engine will produce vibrations after starting. If the connecting rod is severely deformed, the crankshaft will become stuck, and the engine will not start. Below is a detailed introduction about automobile engines: Overview: The automobile engine is the device that provides power to the car, determining its power, economy, stability, and environmental performance. Depending on the power source, automobile engines can be divided into diesel engines, gasoline engines, electric vehicle motors, and hybrids, among others. Others: Common gasoline and diesel engines are both types of reciprocating piston internal combustion engines, capable of converting the chemical energy of fuel into the mechanical energy of piston motion and outputting power externally. Gasoline engines have high rotational speeds, are lightweight, produce less noise, are easy to start, and have low manufacturing costs. Diesel engines have a high compression ratio, excellent thermal efficiency, and better economic and emission performance than gasoline engines.

[Joseph]

I was driving my old Santana when the connecting rod bent and the car wouldn't start at all. The dashboard lights were all on, but the engine didn't make a sound. I thought it was a battery issue, but even after replacing it with a new one, the problem persisted. Later, when I towed it to the repair shop, the mechanic opened it up and found the connecting rod severely bent. He said it was caused by overloading during long-distance driving and insufficient lubrication. Attempting to start it could have made the piston pierce the cylinder block, completely destroying the engine. The repair cost me several thousand yuan. So, the lesson I learned is: if you suspect a connecting rod issue, never try to start the engine. Just get it towed to a reliable shop for inspection—that's the safest approach.

[BarrettLee]

From my repair experience, a bent connecting rod means abnormal piston movement. When starting the engine, the crankshaft rotation may get stuck or cause knocking sounds. In severe cases, it can completely destroy the engine's internal structure, such as piston fragmentation or cylinder block cracking. I recommend first checking the engine compartment for any abnormal noises or oil leakage traces, then directly cutting off the ignition system to avoid starting. The safer option is to call a tow truck to send it to a repair shop. Let the technician use a diagnostic tool to confirm whether connecting rod replacement or overhaul is needed. Otherwise, forcing a start could turn a minor issue into a major repair with skyrocketing costs.

[SanJoy]

My little car had a similar issue before. The connecting rod was bent, and as soon as I started the car, it made a rattling noise without any response. I was so scared that I didn't dare to try again and immediately called for roadside towing service to send it for repair. The mechanic said that after the bending, the piston position was offset, and the ignition couldn't fire at all, which also damaged other parts. It's advised that if you encounter a similar situation, don't risk starting the car. Instead, park the car in a safe spot first and call for help. Turning a small problem into a major accident isn't worth it.

[FinleyDella]

Considering the budget issue, if the connecting rod is bent and you start the car, the repair cost may skyrocket from a few hundred to tens of thousands. The expanded scope of engine damage is not worth the risk. A friend of mine had to replace the entire engine after a forced start, which cost a significant amount of money. Therefore, the safest and most cost-effective solution is to avoid ignition and arrange for a tow truck immediately.