Is It Harmless to Rev the Engine to 4000 RPM in Neutral?

[DeNatalie]

Revving the engine to 4000 RPM in neutral can damage the car. It is generally not recommended for drivers to aggressively press the accelerator in neutral, as this can harm the engine, affecting its lifespan and reliability. The accelerator, also known as the throttle or gas pedal, is the control device that regulates engine power. Neutral refers to the state where the vehicle's gearshift is not engaged in any forward or reverse gear, completely disconnecting the transmission from the engine. In manual transmissions, neutral is the middle position, while in automatic transmissions, it is marked with an 'N'. Revving the engine to 4000 RPM in neutral can have the following effects: it subjects the engine's moving parts to significant inertial forces, compromising reliability and lifespan; the engine's RPM rises sharply, causing the moving components to endure forces exceeding normal operating conditions; it increases the risk of cylinder scoring and bearing failure; and it places excessive load on the transmission gears, which can lead to gear damage in severe cases. Prolonged revving in neutral can result in incomplete combustion. If these unburned gases accumulate outside the cylinders and reignite, it may even cause the vehicle to catch fire. Additionally, revving in neutral generates carbon deposits. Frequent or prolonged revving accelerates carbon buildup, which can severely clog the catalytic converter, leading to vehicle malfunctions.