I have been dealing with the problem for 2 years now. I would like to fix it before winter. This only happens when the engine is cold. Maybe below 32 deg F. The problem goes away when the engine warms up. Here is what I did last winter.

Disconnected the linkage as close to the IP as I can get. Start the engine, grab the disconnected linkage that goes down to the IP and push down on it, and it sticks. You can watch it very slowly return to idle position. Or you can pull it pack to the idle position with a lot of resistance. Let the engine run for 5-10 min to warm up. Push down on the linkage, the linkage returns to idle immediately .

I have read a handful of posts regarding this same problem but have not read if there is a fix for this. Anyone out there know about this?

Thanks for the reply Charlie