My 2007 Pilot was running rough, throwing misfires. Changed the plugs, they were well worn with Bosch plugs. Started hard right away, but once it did, worked fine. When driving, it runs great but when idling for too long it threw a code, and idles rough like the misfire. Give it a little gas, it straightens right out. I did reset the codes when I changed the plugs and haven't had time to check it again yet. It has thrown O2 sensor problems before. Maybe a buildup on the sensors is throwing it off. When I changed the plugs, I did see some water on the the coil pack stem to the plug, but it hasn't rained (and it's a rear one). I did lubricate the seal on the coil pack. I'll check the code tonight.