Actor based on WheeledVehicle is 'immune' to any force when stationary

We are currently working on a racing game and, thus, using the WheeledVehicle class as parent class for the cars, which the players drive. Since our game features Power Ups (because Power Ups are awesome! Offtopic, I know, but true!), we use various ways to “move” the cars beside normal driving (Explosions, Boosts…).

However, while doing so we observed a very curious phenomenon:

No matter if we use a Thruster (component of car), AddForce (to the mesh) or fire an inpulse with a RadialForce, whenever the affected car is stationary (does not move/drive), there is no effect at all. The only exception is the impulse, which shows an affect on stationary cars. But still, the effect is much less than on a moving car, hit with the same amount of force.

Does anyone else have the same issue or even a solution how we can change that?

Looks like this issue is not a coincidence but a bug in PhysX:

Thread in forum which covers the topic (see “Stationary vehicles refuse to move on impact” in first post)

Backlogged issue on the topic (plz vote^^):