Sputters alot

Thank you very much.
Fuel pressure test
Key in on position:
Test1: 48-50psi
Test2: went to 50 then dropped to 42psi.
Engine running:
Test1: 40psi
Test2: bouncing between 38-40psi

Fpr appears fine under inspection, no gas on the vacuum line side.

Crossed paths with the mechanic that had me clean the throttle body and he suggested I skip today’s fuel test. Figured I will need to hook it up to a machine for more in depth inspection. But that is out of my price range.

So what is my next step to my never ending struggle?

I skipped the wires when I did plugs simply because the plug wires appeared to be in really good shape, especially inside the boot of the wires. Most did not have the metal heat protection on them anymore like stock. And one plug was different from the rest. Looked like the person before me had changed wires at some point but could not get but one plug out. Which I could understand, without an abundance of swivels and extensions and also a jack that would have been a serious pain.
Also, I would have changed coil packs but when before I changed plugs it was just one cylinder that had suddenly appeared prominent to an obd2 scanners besides my random misfire. If the coil pack were bad I would expect two cylinders because they are “piggy back” style coil packs. And the ICM has not been looked into because its price is 1/4 of what I paid for the car, and I do not really think the parts stores goons around here know what they are doing when it comes to testing them. And I do not own a multi-meter. So I will not be able to read the low voltages going through them. The testers I have only read 12 volts and up.

Here is a video of a start up on the gauge cluster. I applied no pressure to either pedal and sat still. The oil pressure gauge is crazy because the harness is wrong at the front of motor. And as far as the voltage gauge, it reads funky but my alternator puts off 13.9 volts at battery when tested at parts store, and appeared healthy. The rpm's is the main thing.

Okay, I know exactly what your talking about. When I cleaned the throttle body I pulled it off and cleaned it a little too. Did not really inspect o-ring. Just left it as a questionable replacement needed. Will look into pricing and get to work.
Thank you very much.

Okay, the IAC got changed a couple days after my last post. I cleared codes and about a week after that I got the codes p0172 and p0175. The change in running condition was huge initially. After about three weeks I started to notice the rpm bounces periodically. I have cleared the codes a few times and it comes back about each week.
Recently it has seemed like it stutters before it gets moving correctly off of a stop. Getting out and going a little faster helped the first couple times with rpm bounce and stutters after that, not so much. Rpm's still bounce periodically.