1999 I30 - Intermittent P1320 Ignition Signal

[golden_retriever]

Hello - My '99 I30 (110,000 miles) has just developed what appears to be a #1 (rear far left cylinder) misfire at idle RPM levels (but still very intermittent). It didn't throw a code until yesterday afternoon (when it was raining), which turned out to be a P1320 .

After reading some similar posts here, I pulled the coils and plugs last night and the plug in #1 came out wet with what appears to be oil on the threads. I replaced the plugs and the coil on #1, and I had the same problem after warming it back up (still intermittent though). I pulled the plug and it appears to be clean this time. I am stumped about what could be causing this - the coils all test OK, and spark seems to be making it (at least intermittently). Any suggestions or ideas? Thanks so much in advance!

[golden_retriever]

Update: I was informed (thank you!) that the wetness on the spark was probably just unburned gasoline coating the plug. I also heard that resetting and clearing the ECM might help (via disconnecting the battery) - I did clear it and it seems to be running well now (over 100 miles). I will post an update if any issue reappears.