What Causes the Car Body to Shake After Starting?
2 Answers
Here are the reasons why the car body shakes after starting: 1. Unstable oil pressure—abnormal fuel pump supply pressure or incorrect readings from the intake pressure sensor can cause the car body to shake. Solution: Check the oil pressure and replace components if necessary; 2. Aging engine components—if the engine mounts are faulty, vibrations can be transmitted to the steering wheel and cabin, causing shaking at idle. Solution: Replace the components; 3. A common cause is a dirty throttle body or excessive carbon buildup in the fuel injectors. When there is too much carbon buildup inside the engine, the gasoline sprayed by the cold-start injector can be largely absorbed by the carbon deposits, resulting in an overly lean air-fuel mixture during cold starts and difficulty starting. Solution: Clean the fuel system and remove carbon deposits from the idle control valve.
There are quite a few reasons why a car shakes after starting. I remember when I used to help friends with car repairs, this was a common issue, mainly in the following areas: problems with the ignition system, such as worn spark plugs or faulty ignition coils, causing misfires and engine misfires; issues with the fuel system, like clogged fuel injectors not spraying fuel, leading to uneven air-fuel mixture and shaking; excessive carbon buildup on intake valves or the throttle body affecting air flow and causing unstable starts; if the engine mounts are broken and can't absorb vibrations, the whole car will shake; in winter, cold starts make carbon buildup issues worse, resulting in more noticeable shaking. My advice is not to panic—first, check if the engine warning light is on, and take a quick look at the spark plugs or air filter. For prevention, regular maintenance like cleaning carbon deposits every 10,000 kilometers and changing the fuel filter on schedule can significantly reduce the chances of this happening. Safety-wise, ignoring it for too long could lead to more severe engine damage, so addressing it early saves both hassle and money.
