You guys called it, the weak firing was likely due to water intrusion and somewhat loose fitting caps. The washers on all four plugs were starting to rust. New plugs along with the 24K schedule and it's running like a top again.
I did the charcoal canister line delete along with the regular scheduled items and I'm really not sure if it's ever run this strong before. Has anyone here done the canister line delete in isolation and noticed a big difference? This is the line that runs into the right throttle body, just remove the line and plug the hole.