What are the causes of vehicle jerking?
3 Answers
The causes of vehicle jerking are: 1. High engine idle speed; 2. Improper adjustment of the throttle cable or throttle position sensor, resulting in high main oil circuit pressure; 3. Delayed upshifting; 4. Cracked or loose vacuum hose of the vacuum-type throttle valve; 5. Faulty main oil circuit pressure regulator, causing high main oil circuit pressure; 6. Stuck shock absorber piston, unable to dampen shocks; 7. Missing one-way valve steel ball, leading to fast engagement of shift actuators; 8. Slipping shift actuators; 9. Non-functioning oil pressure solenoid valve; 10. Faulty ECU. The solutions for vehicle jerking are: 1. Clean the oil circuit and throttle body, replace the throttle hose; 2. Replace the shock absorber; 3. Replace the engine oil.
Last month while driving on the highway, I experienced sudden car jerking—it felt like the vehicle abruptly surged forward then slowed down, startling me so much I nearly hit the guardrail. After investigating, I realized it might have been due to spark plugs with excessive carbon buildup from prolonged use failing to ignite properly, or clogged fuel injectors disrupting fuel flow. For automatic transmissions, issues with the clutch or control module can cause even more pronounced jerking during gear shifts, especially noticeable when accelerating or climbing hills. Later, replacing some parts at the garage solved the problem without costing much. For safety, I now check the engine and transmission oil monthly to prevent minor issues from escalating. I advise everyone not to overlook slight abnormalities and address them early.
As someone with some mechanical knowledge, I've analyzed the common root causes of car jerking. Most cases stem from ignition system failures, such as insufficient combustion due to worn spark plugs or unstable ignition coils. On the fuel side, insufficient fuel pump pressure can cause uneven fuel injection, leading to engine shaking. Air-fuel ratio imbalance is another possibility, like when a faulty mass airflow sensor affects the fuel-air mixture. For automatic transmission vehicles, jerking during low-speed driving or sudden acceleration often comes from torque converter wear. Personally, I use an OBD scanner to read trouble codes - it's cost-effective and efficient. Preventive measures include using high-quality gasoline to reduce carbon buildup, annual throttle body and fuel injector cleaning to ensure system stability. Early maintenance can save significant repair costs and time.
