What Causes the Car to Jerk When Starting?
1 Answers
When starting, especially when the engine is cold, the car jerks, which is usually caused by dirt on the throttle body. Below are the reasons why the car jerks when starting: 1. Carbon buildup causes the throttle valve to rotate less responsively, affecting the accuracy of the air-fuel mixture parameters or preventing sensors from accurately providing feedback to the servo. Cleaning the throttle body can resolve this issue. 2. It may be due to excessive carbon buildup in the engine. Below are the related symptoms caused by carbon buildup in different parts: 1. Cleaning the throttle body mainly addresses unstable engine idling and stalling. 2. Excessive carbon buildup in the combustion chamber: Increases the engine's compression ratio, creating multiple hot spots, leading to pre-ignition and knocking, shortening engine life, and significantly reducing engine power and fuel efficiency. 3. Carbon buildup on the fuel injectors: Causes uneven fuel injection across cylinders, resulting in engine shaking or stalling. 4. Excessive carbon buildup on spark plugs: Causes spark plug misfiring, leading to engine shaking. 5. Excessive carbon buildup on the throttle body: Causes unstable idling, reduced power, or even stalling. Check if the idle control valve has excessive carbon buildup, leading to this issue.
