What causes unstable throttle with jerking movements in a car?

[DeLane]

It could be a fuel supply issue. If the fuel pump pressure is insufficient, it may be due to prolonged delays in refueling causing premature aging and damage to the fuel pump. Replacing the fuel pump is recommended. Below are relevant explanations: 1. Clogged fuel filter: If the fuel filter is clogged or leaking, it can also lead to insufficient fuel supply, resulting in jerking movements when accelerating. It's advised to replace the fuel filter and test drive to check if the issue resolves. The fuel filter typically removes large particulate impurities from gasoline, improving fuel quality, and generally requires replacement every 1-2 years. 2. Clogged fuel injector: This can result in poor fuel atomization, potentially causing excessively lean air-fuel mixture and leading to single or multiple cylinder misfires, with noticeable engine idle and acceleration vibrations. After removing the fuel injector, use specialized testing equipment to evaluate performance (usually by measuring fuel injection volume per unit time and observing atomization effects). Note: During disassembly, ensure components are placed in order and reinstalled correctly. If replacing with new fuel injectors, ECU matching is required.