I purchased this on amazon and will have it thursday:

I edited my previous reply to add an interesting test I did involving drive vs neutral, I'm not sure if you saw it.
In drive and reverse the rpm is 550 with MAF reading 7.2~ and almost zero misfires
In neutral and park the rpm is 630 with MAF reading 6.5~ with misfires (all of my tests have been on park so far)
Doesn't this seem a bit odd?

 

Not sure about the big A part. may work ok. Personally, I would buy a good used OEM part to make sure another variable is not introduced.The Oetiker clamp that holds the bellows to the plastic bridge is narrower than a worm gear hose clamp as pictured.After install if it still is crazy, use the brake clean spray method on the connection points.

Idles seem normal. When you put it inD or R the pcm will crack the throttle, so rightfully so, the air flow will go up a teeny bit. The car would stall otherwise. Now when the air flow goes up, the manifold absolute pressure will go up slightly (slightly LESS vacuum). No misfires may mean the small vacuum leak you have now has a smaller effect, as any vacuum leak becomes a smaller percentage of the overall air flow into the engine.

Most vacuum leaks lose their influence as engine speed and load goes up.

To confirm the throttle is opening in D and R, set your scan tool to the PID: throttle position in %. You should see a small change in % when you go into drive. Also, do not forget, your car is interlocked so you have to apply brake to put it in D or R. The vacuum boost is activated, which will increase MAP slightly, but with little air flow for combustion.

 

It’s a little difficult to hear the video clearly but it sounds a little “off”...maybe I hear an echo but maybe others can chime in and see what they think...reread your original post and with your smelling gas it still may be ignition related...coil packs are pretty bulletproof on these cars but never say never...maybe you can pick up a cheap spark tester...one that you can adjust the KV setting...set it for 35 KV and see if the spark jumps while cranking...does it only misfire at idle ??...if you power brake it does the misfire go away ??...I did a cranking video below !!

 

Sad to report that the new air connector did not fix the misfire issue. I think it might have been sucking in more air through the MAF instead of the leak now, however, because the MAF reading did seem slightly higher than before which is good, but I didn't get to do a lot of testing today at temp. I can't work on the car for the next week so I will resume investigation after then.
For the time being I'll here's some more info about my car to consider.
I did overheat my car one time this summer before I put in a new radiator. Maybe that could have caused something to leak? Piston rings leaking? Idk. Maybe a compression test should be done.
The previous owner did leave one vacume line cut on the secondary air pump that took me a year to find. The same time I reconnected that was roughly the same time I originally started getting P0300 cuz I remember complaining about fixing one CEL just for another (P0300) to pop up haha. I don't remember if I fixed it before or after I got P0300 for the first time, however, so I don't know if that was related at all, but it is worth noting that there was front end damage and mystery issues around that area and other places too when I got the car.
When I get back I'll leave the car unplugged for a few hours and try to let it relearn and do more investigations based on the data after that.
Thank you everybody for your help investigating this issue... I will solve it some day!
~Tyler

 

Okay so getting this rolling again... Today I took out plug #3 (drivers side, second to front of car) and took some photos you can view here: https://imgur.com/a/tR03yxE
This plug has been in the car for a few months now. It certainly doesn't look as bad as my old plugs. It's a little black around the metal but the ceramic part looks to be fine. It seems more like normal carbon build up.
I did try leaving the battery unplugged for a bit to see if it reset settings but no luck.
The fuel trims seem to be overall fine now. I think the max I saw was like a 4% and even lower under higher rpm's, possibly due to the new intake piece I put on.
Sometimes I can very noticeably smell fuel, and still the car does burn oil a bit.
I still get a lot of random misfires on all cylinders.
More dead ends it seems like.

What do you mean 'power brake it' ? I'll see about a spark tester.

 

Power brake = one foot on the brake and one on the gas

 

While in neutral right? Otherwise that just sounds like a fun time lol. Also I hooked up a spark sensor to the plug 5 and took a slow mo video that had a misfire in it (obd2 reader said misfire during video on plug 5) and i didnt see any abnormalities in the sparking when looking at the slow mo video. I would say that probably eliminates coil packs or spark as an issue. Maybe I need to test my fuel injectors? Compression too possibly?

 

Updates?

 

Car is still misfiring at idle, last checked last night.