Plot hole: James appears in every episode before his introduction in "Thomas and the Breakdown Train." Also, James is supposed to be black, because at the end of the episode, James is told he will get a different coat of paint. (He is also black in the book).
Plot hole: How could Gordon's driver tell the station master that Gordon couldn't get up the hill? There are no phones on Gordon's hill.
Plot hole: When Duck and Diesel leave the shed, Diesel follows Duck instantly, but the tracks they are on both lead to the turntable. As they are on different tracks to each other, it would be impossible for Diesel to follow Duck that quickly as the turntable could only be set to one track at a time.
Plot hole: Percy was blamed for being on the coal tipper when it was Arry, Bert, and Henry's fault. None of the three got consequences. Also, why would the workmen tether Percy or even activate the coal tipper when they knew he was an engine?
Plot hole: Bulgy is seen in his season 3 paint job, but in Bulgy Rides Again he's a veggie bus.
Plot hole: When Gordon crashes into the goods train, it is not being pulled by an engine. So why is it just sitting on the mainline and not on a siding?
Answer: He was in the water.