Does accidentally revving the engine in neutral harm the car?
2 Answers
Accidentally revving the engine in neutral does not harm the car. Short-term revving in neutral has no impact on the vehicle, but prolonged revving can be damaging. Extended neutral revving can cause severe incomplete combustion, and if these gases accumulate outside the cylinders and ignite, it may lead to vehicle self-ignition. Although the gear is in neutral, the engine's power continues to drive the transmission's input shaft through the clutch. In this state, revving the engine affects the input shaft, intermediate shaft, and other constantly meshing gears, while the output shaft and gear synchronizer remain inactive. Prolonged neutral revving gradually increases damage to the transmission, visibly harming components such as input shaft bearings, synchronizer gears, and synchronizers, leading to part wear, burning, and transmission noise issues.
As a veteran driver with over a decade of experience, I once accidentally revved the engine in neutral at a red light, causing the RPM to skyrocket instantly with a roaring engine sound that gave me quite a scare. This operation doesn't cause significant damage to the car—it's mainly the engine idling without load, akin to letting the machine warm up without doing any work. However, it wastes fuel and slightly accelerates component wear. An occasional mistake isn't a big deal, but make sure not to make it a habit. Doing this long-term could lead to engine overheating or carbon buildup issues, affecting its lifespan. It's advisable to drive steadily, always confirming the gear before accelerating, which can also save on fuel costs while protecting the car. Regularly check the engine cooling system and oil condition to ensure everything is in good order.
