there could just honestly be alot of reasons that there could be a misfire

 

Could you list any that i havent covered yet?

 

IM Gasket, Put a bead light to your injecter wires to make shore you getting a proper pulse the computers are known for dimming them out, Cat Convertor, Mouse nest under the dash, etc.......

 

^sounds good

 

ok, will do this...im just concerned that since it happens underload around 3-4k, that it might not happen at idle...but i guess it might be and just not be apparent...Ill look for mice too...and althought I doubt it, i will drop the cat and take a look...
Thanks for responses...will report back in day or so if i manage to fix it..
oh and i guess ill grab another IM gasket from autozone, as im sure itll break when removing to check..

 

i usually break the gaskets when i remove them

 

Since you have a pocket DSM thingy can you check fuel trim and O2 output. See if it goes lean while the miss occurs. Gasket leaks.

Also check compression and leakdown if you can. help pinpoint any mechanical problems.

Also check vacuum at idle. Basic engine condition test.

 

I checked o2 voltage, during the missing the voltage drops to like .30ish-.40ish volts...seems lean to me..didnt check trim though, cause i plain dont understand them :P
Compression test came out ok, with cyl one being lowest but not by more then 2-5psi diff from rest...havent done leakdown cause its a pain, but maybe ill have to...
vacum at idle was 19-20 shakey needle thing, but not a major fluctuation...

 

by your first post, your fuel pressure is actually a bit low, try the gage on it while driving and see if it drops off when it starts to miss

 

What causes the PCM to realize there is a misfire in the first place?

Like what sets the code?

I would say lack of fuel pressure, or the regulator is looking for a way out.