Originally Posted by Stewart_H

Sounds like you have a bad COP (Coil On Plug) that fires intermittently.

Clear the code and then swap the COP's on the number 7 and number 6 cylinder to see if you get a P0306 code: cylinder 6 misfire. If you do, then you know you have a bad coil. Just buy a replacement COP and put the new one on. Don't spend hundreds of dollars at a dealership for something you can do in about 7 minutes.

It's possible you have a bad plug in that cylinder, but it's more likely a bad coil.

Stewart