Misfire issues

Hey guys, per my previous post regarding leaning issues, I have managed to solve that with what was a rather stupid thing. Apparently there was a check valve on the vacuum line that had no business being near my car in general.

 

Anyway, that issue has been resolved and my AFR holds solid as it should. However, now I have misfiring issues. Beginning with a weird roughness in cyl.3 under idle, usually will go up to 4 count but occasionally as high as 8. Once in motion it never appears again.

 

Now the more important issue, I developed intermittent misfires in cylinder 2 (primary and roughest) and cylinder 1. Usually appears at around 4500 to 5000 rpm in 3rd at around 10 psi, and at an even lower rpm in 4th gear. Roughness for cyl.2 measures as high as 14 count. I had thoughts it may just have to do with my battery since it was just about dead but I replaced it and still get the idle roughness.

 

I ordered NGK step colder plugs and should be getting them Monday with the intent to install as soon as I can. Also will be doing valve cover gaskets and later on the timing belt (without water pump)

 

In the meantime I'm seeking any sort of help, has anyone experienced these types of intermittent misfires? I'm not throwing any misfire related codes, I did have one code for exhaust temp but that's because the tuner hadn't coded that out. BUT I did get one weird code the other day for AFR too rich when it has been holding steady st 14.3-14.7 in normal load and 11.14 at WOT.

 

Nonetheless any help would be greatly appreciated.

 

Apologies for the super long post and thanks in advance!

Btw just noticed the typo in title

i need help!!

Change the plugs, then my next step would be new/cleaned injectors and/or new OCVs depending on your miles

Plugs come in Monday, hopefully that makes things better. Will not be cleaning injectors, instead waiting a bit and gonna upgrade since I'm dropping a VF52 soon