Istio Injected Sidecar cannot connect to K8s API Server (refused)

Dear Folks,

I am trying to install Gitlab having istio enabled. I noticed a pod, trying to connecto to K8s API Server, but fails with connection refused. This blocks all additional instsallation steps.

The connection to the server was refused - did you specify the right host or port?

When disabling sidecar injection for the namespace, pod starts probably and installation is successfull.

Is there any information I can provide?