I would really appreciate an insight on the below problem.

We have a Mitsubishi Lift in a 22 story building that keeps having the problem of vibration. It feels like the car is stopping and then moving down or up.

We changed the ropes, the guide shoes of the car and counter weight as well as the pulley. We even tested the motor for vibrations and machined the motor bearing's casing. The motor is fine as we've replaced it with a new element yet the problem still exists.

It's been around a month we are trying to solve the problem and so far we haven't been able to stop this vibration and jerking.

I need help. Has anyone faced this problem before?
Can anyone give me an idea of what to check further?

Many thanks,

Hady