I eventually just had the Actuator replaced, and now it's working fine.
But, before I did, it was able to be manually pushed, and it swung over to the proper position. In my case, it was an hesitant drive motor.
IF, you'd like to try that, the Actuator looks like this...
However, there are more than one of these things that operate the system flow, and I don't know where under your dash, to tell you where the proper one is located. You might take a look, and see if you can find the right one.