P0300 but seeing cylinder 4 misfire

[jays99burb]

Been chasing this for too long. Started as #4 mis then went to a multiple cylinder misfire. Following list is items I have replaced to date.
Spider injection, upgraded
Cap, wires, rotor, plugs and cam position sensor
( Plugs are gapped at .45)
Fuel filter
Tps
MAF
Plenum gaskets, was in there already
PCV valve
Upstream O2 sensors
Smoke tested for lower intake leaks, checked out fine.

Something I'm seeing on live data is a low calculated load at idle, less than 7%
I'm not sure where that should be but when I plug my 4.0 ranger in I'm getting around 38% calculated load at idle.
Have not pressure tested the fuel pump yet, it's on my hit list as well as compression test.
I have pulled the valve cover on bank 2 side and all the rockers appear to be doing what they should be. Correct me if I'm wrong but a low load like that could indicate clogged cats?

 

[jays99burb]

Been chasing this for too long. Started as #4 mis then went to a multiple cylinder misfire. Following list is items I have replaced to date.
Spider injection, upgraded
Cap, wires, rotor, plugs and cam position sensor
( Plugs are gapped at .45)
Fuel filter
Tps
MAF
Plenum gaskets, was in there already
PCV valve
Upstream O2 sensors
Smoke tested for lower intake leaks, checked out fine.

Something I'm seeing on live data is a low calculated load at idle, less than 7%
I'm not sure where that should be but when I plug my 4.0 ranger in I'm getting around 38% calculated load at idle.
Have not pressure tested the fuel pump yet, it's on my hit list as well as compression test.
I have pulled the valve cover on bank 2 side and all the rockers appear to be doing what they should be. Correct me if I'm wrong but a low load like that could indicate clogged cats?

It's been a while since I've followed up on this. Fuel pressure 58 key on engine off, 55 truck running. Doesn't drop off after turning the key off. Compression test, over 160psi on all cylinders except #4 that one didn't even give me a reading. Sent a bore scope camera in there, piston looks like it's been getting a steam bath haha could explain why coolant is disappearing and the cat for the bank 2 side isn't getting hot like bank 1. So that brings me to head gaskets. I ordered the high end fel pro kit. I have the dash command app on my phone but I didn't see a PID for the cam crank sync? Is it the bar under the timing bar? Just not clearly labeled? I wanna make sure I'm 100% ready when I tear this old girl apart.