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Rb26 intermittent miss, runs a bit off. Sarted after driving in heavy rain.

Hey everyone. Im a bit stumped and perplexed at this point. I have a 99 stagea 260rs. It has an apexi power fc, other wise stock engine.
Anyways i went with a friend to go look at a cheap Delica an hour away on the weekend, on the drive back it was a nasty downpour. I noticed when i took over driving the engine sounded a bit off at idle when i stopped to switch seats with my friend. Got home and when holding the revs at 2-3k rpms a noticeable intermittent miss occurs. At idle the car sounds off, almost more of a honda sound with a rice can,  same as revving under load it has a riced out honda sound (as funny as that sounds). This all happened after driving in really heavy rain for over an hour. 

It's also revving just  bit higher as well. I noticed the commander will say 900 rpms for current revs while the tach reads about 1050. It sounds like a bit faster idle as well

Only 2ks ago i put in new plugs ngk bcpr7eix, and put on super spark coil packs when i got the car. 

I was thinking a plugin or coil pack got wet. After the rain i have gone and pulled any plug i could find including the ignitor, and dryed with compressed air then applied dielectric grease to each plug as well. No difference. I pulled all the coilpacks and even pulled a plug. I bought new coppers to run, but after pulling the new irdium plugs i decide dto keep them in there as no evidence of  of foul plugs was present.  The plug looked in great shape and no coil packs or plugs were wet. I installed my old set of stock coilpacks and no difference either. I can hear a noticeable miss from each cylinder when i pull each coil pack plug as well so its not one individual/constant miss. 
I have a friend with a spare igniter that i am going to try as well. I'm not really sure what next to do.

I also checked the wiring but didnt seem to notice anything change while checking the ignition harness and plugins.
I was thinking fuel but i dont think so as im not getting a knock but it could be fuel im not sure. The fuel filter is fresh as well but i can change that too. 

When i was going through the apexi fc commander i noticed that the second O2 sensor is sending no voltage or 0.04V so im guessing that's gone. I don't know if that would cause the miss tho.
There is an aftermarket grounding kit that goes to the ignitor as well. I had to put on larger north american terminals and can't get the greatest contact but after adjusting he grounding kit there was no difference.
Any ideas would be appreciated. I'm a bit stumped and i was considering selling my stagea then this develops.
Thanks!

From my experience, R32s are voltage sensitive, so make sure the battery terminals and grounds/earths are good.
Also, does it have standard AFMs? I'd re-solder the pins inside as they're old now.

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