ChaosVehiclePlugin suspension problems

I made a car using ChaosVehiclePlugin, and sometimes it interacts on collisions in unexpected way. Specifically, it is the wheels.

  1. If i hit one car with another, hitting only wheels to wheels just does nothing: both car behave like impact didn’t happen and they just stop all movement. Car that was hit doesn’t not recieve any impulse or forces. I think it is happening because car suspension absorbs impact.
  2. If car rides with some speed and wheel hits small rock or any other obstacle, car gets launched into the air. It feels like this is caused by suspension overreacting; if i lower suspension Spring Rate in Wheel BP, this effects gets weaker.
  3. If i drop one car on top of the other, both cars get launched into the air. No idea what can cause it.

Questions are: how can i change suspension reaction to this events? Where is suspension handled in ChaosVehiclePlugin? I couldn’t find exact file, so i suppose it is handled by chaos somehow. How can i debug this? I want to locate exact reason of weird behavior.
Thanks in advance for any help!