I’ve got a 2001 Lincoln Continental that had a misfire on cylinder 7 but only happens when idling. When it’s moving it will fire normally. I recently had all the spark plugs replaced and coil overs replaced however it still has a misfire. Was told that it would need a new injector on cylinder 7 as well and replacing the seals on all the others. If that didn’t fix it would be the valve that’s gone bad. Super confused as I have taken to two different mechanics who have told me different things.
This is a coil-over. It's suspension part:

I think you mean ignition coil for a coil-on-plug system.
If the problem is the injector, it would should up on a scope. If it was a valve seat, then it would show up on a compression test.
A professional mechanic worth his salt should know how to troubleshoot a problem as basic and common as a misfire.

