Is this belt tensioner bad? This is on the passenger side of the 2.4L K series motor.

When the AC compressor turns on, the tensioner starts going back and forth (between more tension and less tension). You can see the movement in the tensioner even though my camera struggles to capture it a bit.

When the AC compressor is off the tensioner is pretty stable.

The car also has a vibration that occurs when the car is driving and the AC is on. It can happen at slow speed sometimes. It almost always happens at 75MPH if you give it a good amount of gas. It also happens going up hills more than going down hills.

I took videos to show the possible issue:

 

Mine wiggles more than that does with the AC on but it is a cheap after market brand. My index marks in the top video line up. Maybe the experts could help on the torque requirement and as to whether those index marks (if that is what they are) need to line up.
I have found that some of the vibration is from after market eng mounts and installation not done in a particular order. I have put up with the vibration since I got the V for over 3 years and it does not go away with new compressors or the new tensioner, again, cheap after market replacements.

 

I discovered I have a Bando belt on there. Apparently Bando belts have a bit of a bad reputation on Hondas, being too thin and causing vibrations. I ordered a Honda belt and will replace the tensioner with a Honda tensioner while I’m in there. Fingers crossed.

 

I have also noticed that I can step on the gas and add about 50-100 rpm and the vibration goes away. Idle clean up is on my to do list...