08 Tige RZ2 Surging

[kdammen]

I have a 2008 Tige RZ2. It has the 340 Marine Power GM Vortec 5.7L V8. When out today, it would start and idle fine, but struggled to get above 2500rpm. Felt a lot like speed set(cruise) was on. It would surge at times. Sometimes after running full throttle for a minute it would eventually clear up and get near peak rpms. I don't have any alarms or messages, so I don't think it's a limp mode. I'm not sure where to start. Throttle position potentiometer? Or fuel pump/filter? Any suggestions? I'm taking the boat 6 hours away next weekend for a 7 day vacation and need to get this figured out ASAP. Thanks

[kdammen]

I just had my wife move the throttle lever while I watched the throttle body move. I didn't see any erratic motions, it opened/closed fully and smoothly. So I don't think it's a Throttle position sensor issue. I'll try new plugs tomorrow since It's been a year since the last set. The fuel/water separator is 2 years old.