Is It Harmful to Rev the Engine in Neutral Gear?
2 Answers
Revving the engine in neutral gear is harmful to the car. Doing so subjects the engine's moving parts to significant inertial forces, which can compromise the engine's reliability and lifespan. When the car is in neutral, the engine does not output power. Rapidly increasing the engine speed in this state forces components like pistons and connecting rods to accelerate abruptly, generating high acceleration and subjecting them to substantial alternating loads. Prolonged revving in neutral can lead to severe incomplete combustion. If unburned fuel-air mixture ignites outside the cylinders, it may cause the vehicle to catch fire. Incomplete combustion also promotes carbon buildup, which can clog the catalytic converter, leading to abnormal high temperatures. These elevated temperatures may cause wiring to ignite, resulting in serious consequences.
As a veteran driver with over 20 years of experience, I've seen too many people revving the engine in neutral while waiting at red lights or during idle moments, thinking it's just playing around with the car. To be honest, doing it occasionally isn't a big deal, but making it a habit is troublesome. Running the engine at high RPMs without load not only wastes fuel but also increases emissions, harming the environment. What's worse, internal components like piston rings and bearings wear out faster, and over time, the engine's lifespan shortens while repair costs skyrocket. I always remind my friends to develop good driving habits and avoid such unnecessary actions if they want their cars to run longer and more reliably. Thinking back to my first car in my younger days, it needed new parts within just a few years because I often drove like that.
