Uneven drivetrain power

sounds normal. there is a 3 second delay in the energy monitor. you need a scan gauge or equivalent to see what is happening real time

 

well done!

 

Make sure you lubricate the throttle body return spring.

And gurgling in the coolant means there is air in that loop. Be careful there because you could be overheating the engine because of trapped air and you would never know it.

Pick up a scan gauge to monitor engine temp till you can bleed that air out properly.

If going to change spark plugs go to dealer and buy a new valve cover gasket as yours is probably weeping like lots of others including mine super easy to replace when you have it all apart. You may find oil in the spark plug well when you pull the plugs out. Get a hand mirror and look in the wells before pulling the plugs.
When you pull the valve cover off take pictures of the valve train. You will quickly see how well the engine was taken care of when you can see the valve train and if it’s lived on Dino oil or good oil.

I also replaced the windshield rain dam gasket too since you may damage it taking it out.

And since your in there replace the pvc valve. It’s all there easy to get at when you pull that harness back to get at the plugs. Only use exact size wrench when taking pcv out. Many posters destroyed there valve cover using adjustable wrench.

I found on mine both pvc hoses from valve cover to TB had cracked ends. Replaced both hoses.

Make the most of exposing the top of the engine.

 

Or Torque Pro or one of the myriad of phone apps that will do monitoring just fine at a fraction of the cost.