The new ones are Sachs SuperTouring gas shocks. They are replacing the OEM KYB gas shocks.
The problem occurs after the car has been standing for some time.
If I push down and release the rear bumper, the car rebounds as if there is no damping in the shocks.
If I repeat this, the same thing happens.
It's not until the third time that the shocks start working.
One if the reasons I replaced the old ones is, after 45,000 miles, they had developed the same problem, as well as lack of wheel control.
I've replaced shocks (and struts) on other cars before and never had this happen.
At this point I have about 100 miles on the new shocks.
Any suggestions will be greatly appreciated.