stumble at 3000 and oily spark plug (take 2)

[spiritmadness]

I'm not sure why this didn't post with the previous thread but anyway...
Hey everyone out there in TD-land!!

All right, I noticed that when I was driving home today that at about 3000 rpm the car had a stumble. It went away at WOT. This only happened when I was cruising at about 3000. I got home and checked the spark plugs. Plugs 1,2 and 3 all looked like they were fine. They all had a very slight whitish tone to them almost as if they were running just slightly lean. The #4 plug was oily around the electrode. Any guesses as to why? These plugs are all less than 2 months old.
Also, my Dawes device reads as if I am running very rich, (blue light at WOT), but the rest of the plugs don't confirm this. The car seems to run fine at speeds lower and higher than around 3000 rpm. The plugs situation and A/F meter readings are worrying me. Any help with these problems would be greatly appreciated.

-Bryan
91 Spirit R/T
18 PSI FWD cal (spikes to 24 psi)
+40s
3 bar map
255lph Fuel pump
AFPR set to 50 psi static
Large ADFX Front Mount IC
2.5" full exhaust
Spark plugs are the champion RN9YC gapped to .30 with magnacore wires.

[spiritmadness]

I hooked up a multi meter to the wires the Dawes device runs off and with the car off there is a 0.07 voltage already present.

Does anyone have any ideas?

I had the same problem with my # 3 and #4 spark plugs. I took the head off and the head gaskett needed replaced. my blown head gaskett was letting oil get on the plugs causing them to not fire as a result the car would stumble.