What Causes the Jerking Sensation When Releasing the Accelerator Pedal in a Car?
3 Answers
If your car jerks when you release the accelerator pedal, it could indicate an issue with the transmission. First, check whether the transmission fluid is low or has deteriorated. Theoretically, except for CVT transmissions, all other types of transmissions may exhibit jerking sensations. CVT transmissions, also known as continuously variable transmissions, do not have the concept of gears, so there is no gear-shifting jerk. However, due to manufacturer tuning, even CVT transmissions may occasionally produce jerking sensations. For automatic transmission cars, a slight jerk during gear shifts while accelerating is normal, though the intensity varies by vehicle model. If the gear-shifting timing is not well controlled, the jerking sensation can become more pronounced.
I have studied automotive dynamics for many years, and the main cause of jerking when lifting the throttle is usually an issue with the transmission control system, especially in automatic transmission models. When the engine speed drops, if the solenoid valve or valve body malfunctions, it can lead to delayed shifting or uneven clutch engagement, causing the vehicle to shake. This may also be caused by aging or worn transmission fluid or software bugs in the electronic control unit. I recommend that owners check the quality and level of the transmission fluid—if it is cloudy or low, it needs to be replaced. At the same time, observe whether the jerking occurs only at specific speed ranges. For example, if it is more noticeable when lifting the throttle at low speeds, it is likely related to the low-gear logic. Long-term neglect increases the risk of wear and tear, so it's best to use an OBD scanner to read fault codes or consult a professional technician for adjustments. In daily driving, avoiding sudden throttle release and maintaining smooth operation can delay the onset of the issue, but this fault must be addressed early to prevent further damage.
I've been driving for 15 years and have encountered jerking when lifting off the throttle several times. At first, I didn't think much of it, but later my Magotan would shake violently when decelerating on the highway. After taking it to the shop, the mechanic found that the spark plug gap was too large, causing unstable ignition; replacing them fixed the issue. Another time, it was due to severe carbon buildup in the intake system, which caused the mass airflow sensor to report incorrect data. I tried cleaning the throttle body and fuel injectors myself, which helped somewhat. More technically speaking, jerking can also be caused by insufficient fuel pump pressure or a clogged air filter. I recommend that car owners first check their oil condition and filters. If it's not a major issue, cleaning the relevant components can alleviate the problem. If a new car experiences jerking, it might be due to the ECU's adaptive learning not being properly adjusted—try disconnecting the battery to reset it. In any case, don't delay; addressing the issue early saves money and prevents further damage to the car.
