Well you can either throw money at it and pray or find someone who knows what a TPS is. Takes a $5 scanner on a cell phone and a $12 dongle to both monitor and log while driving to review later. A momentary dropout would be exactly like taking your foot off the gas momentarily.
BTW there is a long section on the TPS diagnosis starting on page 9-257 of the '04 factory service manual
ps while I have a '04 Coupe with automagic now my first Crossfire was an '07 Coupe with a six speed. Been there, have the hat.