@papajoeb Happy you got it working.

@fiene2019flight It's an SU5 bug. I expect it's on the 'to-do' list!

@RFpilot Are you leaning the mixture at higher altitudes? At high altitudes, the mixture needs to be leaned (by pulling the red lever back) because there is less air up there. The engine will lose power if it's not leaned properly. Generally you want to aim for peak EGT (look at the EGT gauge near the throttle levers) for best economy or peak EGT + 100 degrees F for best power.

Sorry, I see the problem now -- I purchased the PA-28R Arrow III & Turbo Arrow III/IV Bundle, for which they are only showing:
COMPATIBILITY FSX/FSX:SE/P3D v1-v4
CURRENT VERSION 2.01
https://www.pcaviator.com/store/product.php?productid=21356&cat=0&page=1

On the other hand, they are showing the PA-28R Turbo Arrow III/IV title as:
COMPATIBILITY FSX/FSX:SE/P3D v1-v5
CURRENT VERSION 2.03
https://www.pcaviator.com/store/product.php?productid=21355&cat=0&page=1

So far their download file has not been updated for the bundle.

Almost the same issue here. Using the Turbo Arrow IV in P3D 4.5 with the latest hotfix with a balanced load and fuel but my aircraft banks to the left at least 10 degrees with the yoke centered. I don't have this issue with any other aircraft such as the A2A planes or the JF 152...or any others for that matter.

I am aware of the right rudder needed on take off/climb but my banking issue persists even at 9,000 ft cruise and all other altitudes.

Look out the window! Otherwise no.

(page 67 in the manual) ... "As you approach 4,000ft, place your mouse cursor over the navigation/approach coupler knob and press the middle button on your mouse (this is often integrated into the mouse-wheel). Alternatively, you can use the default key assignment – [Ctrl]+[Z].This toggles altitude hold mode. The autopilot will capture and hold the current altitude (rounded to the nearest hundred feet). A tooltip indicates whether altitude hold mode is engaged.

... The real-life Piper AutoControl IIIB doesn’t feature altitude hold mode but it has been included for convenience".