What Causes Vehicle Body Shaking at 70-80 km/h?
2 Answers
Here are the possible reasons for vehicle body shaking at 70-80 km/h: Ignition system issues: Check the working condition of spark plugs, high-voltage wires, and ignition coils. Poor performance of the ignition system or improper spark plug firing can lead to such symptoms. Unstable oil pressure: If you've already cleaned engine carbon deposits, washed the throttle body, replaced oil pads and spark plugs, but still notice body shaking at idle, it's recommended to visit a 4S shop to check the fuel supply pressure and intake pressure sensor. Abnormal fuel pump supply pressure or incorrect readings/malfunction of the intake pressure sensor can cause body shaking. Engine mount aging: Engine mounts serve as the engine's shock absorption system, absorbing minor vibrations during operation. If engine mounts fail, these vibrations can transfer to the steering wheel and cabin, causing shaking at idle. Severe engine carbon deposits: The most common cause of vehicle shaking is excessive dirt on the throttle body or too much carbon buildup in the fuel injectors.
Having driven for over a decade, I often encounter body vibrations at speeds between 70 to 80 km/h, with the issue mostly stemming from the tires. The most common cause is tire imbalance, where uneven weight distribution on the wheels leads to pronounced shaking within this speed range. Uneven tire wear or mismatched tire pressure can also exacerbate the vibrations. For instance, during a recent long-distance trip, the car shook like it was dancing when the speed reached 75 km/h, and upon inspection, I found an old tire had developed a bubble. Another possible cause is slight wheel rim deformation, especially after hitting a curb. I recommend regularly checking your tires yourself—feel the surface for any bulges, ensure the tire pressure is even, and when vibrations occur, try accelerating slowly without load. If the problem persists, visit a professional shop for wheel balancing or tire replacement to ensure safe driving, as high-speed risks are too significant.
