What are the reasons for the car not accelerating when the throttle is pressed?

[VonVivian]

The reasons for the car not accelerating when the throttle is pressed are: 1. Throttle malfunction or excessive carbon buildup on the throttle; 2. Fuel supply system failure; 3. Poor quality gasoline. Methods to address the issue of the car not accelerating when the throttle is pressed: 1. Check gasoline pressure and cleanliness, replace the gasoline filter; 2. Inspect the ignition system, spark plug wires, and spark plugs; 3. Check cylinder pressure and whether the engine is misfiring; 4. Examine the intake and exhaust pipes for blockages. The throttle, also known as the 'air valve' or 'throttle valve,' is the control device that regulates the engine's power (thrust). In piston aircraft engines, the throttle controls the carburetor's throttle opening to regulate the cylinder's filling volume, thereby determining the engine's output power.

[MatteoFitz]

I've encountered this issue of the car not accelerating properly several times over my many years of driving, and it's mostly due to problems with the fuel system. The most common causes are an aging or clogged fuel pump—if the pressure isn't sufficient, fuel can't reach the engine, and the car naturally won't pick up speed. Another frequent issue is excessive carbon buildup in the fuel injectors, which prevents enough fuel from being sprayed, leading to the same problem. Additionally, if the air filter is dirty or blocked, the lack of oxygen supply makes the engine run poorly, resulting in sluggish acceleration. During one long road trip, my car suddenly lost power, and upon inspection, it turned out the fuel pump had failed. Replacing it restored the car to normal. I recommend regularly cleaning the throttle body and replacing the air filter to avoid being stranded at critical moments. If you do encounter this situation, pull over immediately to check, as safety should always come first to prevent accidents.

[McJake]

As a car enthusiast, I've noticed that poor throttle response is often related to the ignition system. For instance, excessively worn spark plugs causing weak ignition can lead to incomplete cylinder combustion, resulting in sluggish engine acceleration. Similarly, cracked ignition coils failing to generate sparks will also affect performance. Additionally, sensor malfunctions like inaccurate throttle position sensing can cause the ECU to misjudge acceleration demands, making the throttle unresponsive even when pressed hard. During my own car modifications, I once encountered a faulty oxygen sensor that prevented speed increases – a simple replacement of this small component solved the issue. I recommend checking diagnostic codes or using an OBD scanner during spare time to detect such problems early, which can save significant repair costs. During routine maintenance, pay special attention to spark plug lifespan and wire aging issues.

[Lorraine]

When I was young, I often made this mistake while driving, and looking back now, it was mostly due to neglect in maintenance. Problems with the drivetrain were especially common, such as worn-out or slipping clutch plates in manual transmissions, which would prevent power from reaching the wheels and result in slow acceleration; the same goes for torque converter failures in automatic transmissions, where insufficient oil pressure makes acceleration difficult. That time on the highway when I pressed the gas pedal and got no response, I pulled over and found the clutch was excessively worn—fixing it prevented a major accident. I recommend new drivers pay attention to regular clutch inspections and avoid prolonged half-clutch driving. For safety, if your car can't pick up speed, turn on the hazard lights and slowly pull over.