What are the possible causes of weak engine acceleration?

[Cox]

Here are the reasons for weak engine acceleration: Fuel system failure: Many people believe that throttle carbon deposits affect engine acceleration performance. However, throttle carbon deposits mainly cause unstable idle speed and have little impact on acceleration performance; A clogged or waterlogged air filter reduces air intake, leading to an overly rich air-fuel mixture, incomplete combustion, and poor acceleration. In this case, the exhaust pipe emits heavy black smoke; Cracks in fuel lines or loose joints causing air leaks, insufficient fuel pump pressure leading to poor fuel supply, affecting acceleration; Poor atomization or clogging of fuel injectors results in poor or non-functioning cylinders, affecting acceleration performance. The exhaust pipe may emit black smoke. Fuel quality is another factor; if the fuel contains excessive water, the exhaust pipe will emit white smoke. Electrical system failure: Issues with the mass airflow sensor reduce air intake, causing the air-fuel mixture to be too rich or too lean, affecting acceleration performance; Damage to individual cylinder spark plugs, meaning misfiring cylinders, affects acceleration performance. Additionally, leaking ignition wires can cause issues; excessively high coolant temperature or a faulty temperature sensor also affects acceleration performance; a clogged catalytic converter or faulty oxygen sensor can also lead to poor engine acceleration.

[StKing]

Engine acceleration weakness is really frustrating. As someone who has been driving for over a decade, I've found many causes for this issue. The most common problem lies in the ignition system – aged spark plugs or burnt ignition coils can lead to insufficient spark. My car experienced this last time with sluggish acceleration, and after inspection, it turned out to be clogged fuel injectors restricting gasoline flow. Restricted air intake due to a dirty filter or leaking intake pipes can make the air-fuel mixture too lean. Exhaust system issues like a blocked catalytic converter can also hinder exhaust flow and reduce power. Additionally, faults in the ECU control unit or malfunctioning sensors such as oxygen sensors may misjudge the air-fuel ratio. Mechanical wear like loose piston rings can also sap power. It's advisable not to ignore these signs – failing to accelerate uphill can be dangerous. Regular maintenance like replacing spark plugs and cleaning fuel injectors can prevent problems. Pay attention to fuel quality and engine sound changes while driving.