What Causes a Car to Shake on the Highway?
2 Answers
Here are the specific reasons why a car shakes on the highway: 1. Engine carbon deposits: The throttle valve or fuel injector is more prone to carbon deposits. Therefore, when the vehicle experiences shaking, the first step should be to check the throttle valve and fuel injector. If the throttle valve is found to be excessively dirty or the fuel injector has too much carbon buildup, they should be promptly cleaned using fuel injector cleaner and throttle valve cleaner. 2. Engine mount failure: The engine mount is responsible for absorbing the slight vibrations generated during engine operation. If there is an issue with the engine mount, these vibrations will be transmitted to the steering wheel and the interior of the vehicle, causing shaking during idle. Starting the vehicle's electrical system is most likely to cause shaking, as the engine will increase its load due to the activation of the electrical system, leading to a drop in idle speed.
I've been driving for over twenty years and have encountered several instances of high-speed shaking. The most common cause is improper tire balancing, especially right after changing or repairing tires. When the wheel speed gets high, the shaking becomes quite severe, with the steering wheel vibration being the most noticeable. Sometimes, the entire car body shakes. Another cause is wheel rim deformation, such as after hitting a curb, which can also lead to shaking at high speeds. If there's an issue with the drivetrain, it's particularly noticeable in rear-wheel-drive cars, with the entire chassis vibrating. Warped brake rotors are also a frequent issue, where the shaking worsens when braking. Once, my tires wore unevenly, with one side thicker than the other, and the wheel alignment was off, making the car wobble like it was dancing. In these situations, I always slow down to a safe area first, then carefully assess which part is shaking.
