What are the consequences of revving the engine in neutral gear?
3 Answers
The consequences of revving the engine in neutral gear include: 1. Incomplete combustion; 2. Carbon buildup; 3. Clogging of the three-way catalytic converter. The working principle of the throttle is: Pressing the throttle pedal directly controls the throttle valve, increasing its opening. This allows more air to enter the engine, and the ECU commands the fuel injection system to inject more fuel, thereby increasing the engine speed and accelerating the vehicle. Precautions for using the throttle include: 1. Press and release the throttle pedal gently and smoothly; 2. Coordinate the clutch release with throttle application promptly and precisely; 3. Select appropriate gears to ensure the engine operates mostly at medium speed and larger throttle openings for fuel efficiency; 4. Before stopping or turning off the engine, release the throttle pedal first and avoid suddenly revving the engine in neutral.
I've been driving for decades. When I was younger, I often revved the engine in neutral just for the thrill of hearing it roar. But the consequences really aren't worth it: not only does it waste fuel, but high engine RPMs can accelerate wear on pistons and bearings. Doing this long-term will shorten your engine's lifespan. It's occasionally acceptable for warming up the engine in extreme cold, but idling while parked has terrible fuel efficiency—it's like watching money pour down the drain. Plus, if the engine overheats, it might trigger warning lights or trouble codes. Safety-wise, there's no accident risk when the car's stationary, but if you make it a habit, accidentally shifting into the wrong gear while driving could cause trouble. Nowadays, I mostly avoid it—only letting mechanics briefly do it during maintenance to clean carbon deposits.
I think this causes significant damage to engine components. Revving the engine in neutral can push it to 4,000-5,000 RPM. At such high speeds, uneven oil distribution occurs, subjecting bearings and connecting rods to excessive stress, which may lead to abnormal noises or oil leaks over time. It also wastes fuel—high-idle RPM results in incomplete combustion, increasing carbon deposits. Some older cars are prone to overheating, which can damage the cooling system. Economically, it's quite unwise—the wasted fuel could be saved for maintenance. Avoid unnecessary revving unless under specific circumstances like warming up the engine, but even then, control the duration and RPM. Protecting the engine ensures longer and more cost-effective operation.
