Sudden Quick Flashing CEL, P0300 code

[Envoy10]

So I'm hoping I can get some help/advice on my current problem. I've been noticing lately my Envoy stuttering, bucking at times when driving on an incline, usually between 40-50 mph. I'd either have to slow down or speed up out of that range for it to stop. It hasn't thrown out a code, until today. So on my way to work I get a flashing CEL that lasts a few seconds, then turns off. At this point the Envoy was only a small stutter. Back in December, I had a constant flashing CEL, also a P0301 code. Luckily, I was able to hobble my way to a nearby AutoZone and replace Coil #1, problem solved. I thought this would be the same, maybe not.

So using my Torque Pro app, I was able to retrieve the code, P0300. After doing some research, I checked if any intake bolts are loose. After watching this YouTube video on checking the O2 sensor,

I decided to try it myself using the Track Replay plugin for Torque Pro to see what the sensors are reading as I drive.
The 1st video is me going downhill with my foot off the gas the entire video.

2nd video starts on a flat surface then I drive up the hill I just came down in the first video.

I'm not exactly sure how to read what this data is saying. I do notice my throttle is never fully closed. Also noticed my coolant temp.
Couple more things to add here. I have two broken bolts that have been broken since last summer. Haven't noticed any problems but just wanted to note it. One bolt is the top right bolt to hold the Throttle Body. The other is the bolt on one of my ignition coils.

I did delete the P0300 code before I recorded these videos hoping I would trigger another code, but nothing so far. I'll keep searching for now.

 

[Mounce]

How many miles since last "tune up"?

Plugs are every 100k using acdelco, coils as needed.

 

[Drec]

My 2005 Silverado does that too, it's a misfire. When I encounter this I know it's time to change spark plugs; which don't seem to last as long on the right bank.

 

[Mooseman]

I just went through this with my son's Silvy. It had platinum instead of iridium plugs. The 4.2 is even fussier in that it must use ACDelco 41-103 plugs.

 

[Envoy10]

I did change all spark plugs last summer with the correct AC Delco. This is also when I broke the bolt on the coil pack reinstalling it. I ended up having to put some cardboard between the pack and resonator to get the coil pack to completely sit. Haven't had any problems with it yet but I will check today. I was hoping I would get a code for that coil or any of them. I don't want to just throw parts at it. After clearing the code I can't get a CEL again.

 

[Mooseman]

No water in the plug well of the broken coil bolt?