If the car shakes at idle, I assume you mean it is parked. If that is the case, the engine could be misfiring due to bad ignition components, or worn/broken internal components. You can zero in on the cause by listening to other noises the engine is making (tapping, pushing or pulling air, knocking, grinding, popping, etc.) and paying attention to where the noises are coming from. If you get someone with experience to listen to the car, s/he can rule out several causes also by what s/he DOESN'T hear. Addition: I had the same problem with my 99 passat and what ended up being the problem was a bag ignition module
Could be tires out of balance. Or a bad tire.
you steering wheel starts shaking because you probably have warped roders your shaking will get worse at higher speeds and when pressing the brake
You either have worn steering components like bad inner or outer tie rod ends, or worn lower ball joints. Sometimes a broken belt on a tire can cause shaking, but that's usually at lower speeds.
where is it shaking in the steering wheel or in the seat? shaking at certain speeds can be caused by a busted belt in a tire
they would suddenly shoot forward at extremly high speeds.
Check the entire front end. Wheel bearings, ball joints and tie rod ends can all wear and call this problem.
That would be a tornado. But there is no evidence that speeds get close to 400 mph. The highest known winds in a tornado were just over 300 mph.
You probably need to get your tires balanced. Or replaced. If the bias goes (steel belt breaks or shifts), the car will waddle at low speeds, and the steering wheel will shake at high speeds.
Stop the driver of the van from wandering... be more specific please whats the real issue of the vehicle is it shaking at speeds ?
on most vehicals that kind of shaking is caused by a worn out steering component. steering dampner or idler arm.
It's possible, but unlikely. However it will shake violently at certain speeds and may damage steering gear and tie rods.
Have your truck alligned. Vibrations on low speeds means your vehicle is out of alignment and or worn or damaged suspension parts...