Well i am not aftermarket, but i did notice after this last drift event there was a tear in my rubber thingy covering the wires. And all the brackets holding that MAF related stuff came lose and everything was hanging. I think i am gonna try finding myself a new MAF or at least use someones to see if that helps. I’ll keep you guys updated. Thanks for the help. 
do this!!!
have the engine idle…
-pull the ignition wire off one at a time(there are special insulated pliers you can use)
-see if the engine rpms drop (if they do that means that cylinder is ok based on its got enough compression, fuel and spark to work)
- if the rpms dont drop check to see if theres spark @ that cylinder by holding the ignition wire over the spark plug a small distance away and listen for the “crack” sound that you hear when the spark jumps
im not sure how to cancel out the fuel injectors on these cars but that will help you at least check to see if you have spark on all cylinders
I have spark and fuel, those are not the problem. Especially since from 3500 to redline my engine runs super smooth. Thats why i dont’ know at point in the track day i had problems, because i was in upper rpms whole day. Only on the highway drive home did i notice.
I m thinking its maf, in progress of getting one and putting it in. I’ll update once i do that.
change the mafffffffffffffffffffffffffffffffffffffff
lol, i m workin on it.
I had a stutter problem, fuel filter and a MAF cleaning did wonders. I later had a low rpm missing and roughness that went away at high rpms or when it was cold. Turned out to be a bad injector.
Ohm test the injectors, they should be like 11-12ohms, one of mine read like 43ohms, definetely bad.
Use shitloads of metal penetrant on the injector cap screws, they strip easier than a camwhore.
Hope this helps.
lol use lube on all screws! my sending unit screws are stripped… old ass screws!
im starting to think i have a bad injector… my car is now missing heavily at low rpm… and continuing up till around 4000… how exactly do i Ohm test the injectors?
what was the problem!?
egr valve was broken, serious exhaust leak. There is a pipe running from exhaust to the egr valve on the back of the engine. I started clutch kicking my car more often at driftdays that particular month, and i guess all the engine movement on bad mounts fucked shit up.
I also had a bad cylinder 3. Wasn’t super bad, but did contribute to about 30% of the power loss.
Bad cyl. 3 as in bad compression, bad injector…?
Well, i haven’t cracked the block open, cuz im lazy.
Dropped an sr in instead.
But it wasn’t a bad injector, or spark plug or wiring. It was definitely something internally. My car was leaking some oil via the headgasket. I know this because i played around with injectors, measured their impedance multiple times, switched them back and forth in different cylinders and end result was always the same.
14ohms resistance, and still a bad cylinder 3. Which means, its either some kind of seal or, bearing issue or piston rings or something. I never checked compression, but if i did, it was probbably lower in that cylinder by a signifant margin over the rest.
I don’t care anymore though, I m SR. 
i was having the exact same problem
now shes running much much worse, before it was just at specific rpms, pretty much same numbers as mentioned above.