Please someone help! pulling my hair out
 

Hi folks, I hope there is someone on here who has experienced this issue. I got a 2005 Mercury Grand Marquis that has a miss at idle but runs great on hard acceleration or cruising. I have done the following, New plugs, coils, injectors, intake manifold o2 sensors. cleaned MAF, and EGR valve. I have a miss at idle, I did a power balance test and the IDS shows -20 on cylinders 5,6,7,8 (drivers side bank). No DTCs. Long term trim 1 is +12 and Long term trim bank 2 is -10 I attached the screen shots.
I also unpluged the brake booster and had no effect on idle. I installed a new PCV valve as well. I swapped coils and injectors from side to side as well. the problem did not follow the components.
https://cimg7.ibsrv.net/gimg/www.for...b341281943.png
Idle in gear
https://cimg9.ibsrv.net/gimg/www.for...6674abe4f9.png
Idle in gear

If the problem goes away when RPM is increased, the PCM gets notified more fuel is needed and the condition is gone.
SO,,,,,,,,,,,,,,I would look for a vacuum leak, Could be anywhere.

Thanks, Tomorrow if it is not raining, I will go ahead and plug the PCV, and all of the other vacuum ports on the engine with rubber caps and see if it changes anything. Today I sprayed all of the fittings with Either and it did nothing. If plugging off all of the ports, i will borrow a smoke machine from my work and smoke test the intake system.

This may sound stupid but does anyone think a cracked fly wheel could also cause this one bank to be low on power? I know I am grasping at straws at this point.

I noticed the rpm is really low 632 rpm and the spec is 790-815 and the map sensor is reading 5.21 PSI . Thoughts?
https://cimg8.ibsrv.net/gimg/www.for...84bf82e338.png