What Causes the Car Throttle to Be Unstable and Jerky?

[Eli]

It could be a fault in the fuel supply. If the fuel pump pressure is insufficient, it may be due to prolonged periods without refueling, leading to premature aging and damage of the fuel pump. It is recommended to replace the fuel pump. Below are some related explanations: 1. Clogged Fuel Filter: If the fuel filter is clogged or leaking, it can also result in insufficient fuel supply, causing the car to jerk after pressing the throttle. It is advisable to replace the fuel filter and test drive to see if the issue resolves. The fuel filter typically filters large particulate impurities from gasoline, improving fuel quality, and generally needs replacement every 1-2 years. 2. Clogged Fuel Injector: This can lead to poor fuel atomization, potentially causing the air-fuel mixture to become too lean, resulting in misfires in one or multiple cylinders, and severe engine shaking at idle or during acceleration. After removing the fuel injector, use a specialized tester to evaluate its performance (usually by measuring fuel injection volume per unit time and observing atomization effects). Be sure to remove and install the injectors in the correct order, and if replacing with a new injector, ensure it is properly matched with the car's computer system.