I've noticed my Fitech has the same issue with the TPS. It's 0% at key-on, but after start it likes to settle at 0.5%, rarely going lower again. Luckily it still recognizes that as 'idle'.
I wonder if these systems are being affected by the higher running voltage after-start? 12v vs 13-14v? Might be worth unhooking a field wire while running to see if the TPS goes back to 0?
