I recently bought a Nissan 240 SX SE and have experienced many problems with it, mainly because the dealership's service department has been lying about my car's specifics and what they have done. Anyway, one of my main concerns is whether the engine is suppose to jerk the car when I turn on the ignition. The service guy said that it was normal, but he has already lied about a bunch of other things, like how it is normal for the check engine light to come on when the car is being started if it shuts off in a few minutes (although the owners manual states that if the engine light does turn on at all, there is a problem.) Anyway, tangent aside, is the engine suppose to jerk the car when the ignition is started?

Mine does, but just a bit, if you have alot of vibration then there is something wrong but if there is just allittle when the car is started and it goes away later, i don't think it is a big deal.

It may caused by the knock sensor. I remember I saw sb mentioned somre where.

Oops i thought you said is the engine jerking, not the car, if the vibration is strong enough to jerk the whole car then something is wrong. I tought you had wrote if the engine jerks, becuase my engine does allittle but it is not srong enough to shake the car.