What Causes Engine Power Loss and Dry Roaring When Accelerating Hard?

[FaithLee]

The reasons for engine power loss and dry roaring when accelerating hard are: 1. Aged ignition coils or spark plugs not replaced for a long time; 2. Fuel system malfunction causing low pressure; 3. Excessive engine carbon deposits leading to poor fuel atomization, incomplete combustion, excessive exhaust emissions, and weak engine acceleration; 4. Engine system malfunction; 5. Damaged three-way catalytic converter or turbocharger. A vehicle's engine operates through the coordinated work of three systems: the intake system, ignition system, and fuel system. When any component malfunctions, it may result in reduced engine power, unresponsive acceleration, inability to increase RPM, and weak acceleration.

[DelJulian]

I was also quite puzzled when I first encountered this issue—stepping hard on the gas pedal only to hear the engine roar without gaining speed. Common causes include the following aspects: The clutch or transmission may be slipping, especially in manual transmission vehicles, where worn clutch plates can prevent power from reaching the wheels. If the air filter is severely clogged, the engine is like a person with their mouth and nose covered, unable to inhale enough air. The fuel system is also suspect—low fuel pump pressure or clogged injectors can result in insufficient fuel delivery relative to throttle input. Issues in the ignition system, such as worn spark plugs or faulty ignition coils, can lead to incomplete combustion. A blocked exhaust system, like a clogged catalytic converter, can also hinder performance by preventing exhaust gases from escaping. I recommend first reading the trouble codes to pinpoint the problem. Later, I found that regular maintenance is particularly effective in preventing such issues.

[SadieLynn]

I've experienced a situation where I floored the accelerator in an automatic transmission car but only heard the engine roar with sluggish acceleration. The key issue lies in the engine's power not being effectively transmitted to the wheels. If the automatic transmission fluid has deteriorated or there's a problem with the torque converter, the power transfer efficiency can be significantly reduced. Clutch issues are more common in manual transmissions. Another possible cause is insufficient fuel supply, such as clogged fuel lines or a dirty fuel filter preventing gasoline from reaching the engine. A dirty air filter restricting airflow is also a frequent culprit. The most easily overlooked cause is a clogged catalytic converter - blocked exhaust is like trying to run while holding your breath. I recommend checking these components, especially for older vehicles where maintenance is particularly important.

[VonLevi]

I've experienced this situation before, and it's most likely an issue with the fuel delivery system. The engine roaring without power indicates it's indeed running, but incomplete combustion leads to weak power output. First, consider the aging of the fuel pump, where insufficient fuel pressure fails to deliver enough gasoline. If the fuel injectors are clogged with debris, poor fuel atomization results in low combustion efficiency. A dirty fuel filter can also restrict fuel flow. Additionally, check the fuel pump screen in the gas tank—this small component can also cause fuel starvation if blocked. It's recommended to test the fuel pressure value. Cleaning or replacing the related components usually solves the problem, and the repair cost is relatively low.