Hit Toys james keeps stopping

I think its cause the middle wheel, please help. when i nudge him he goes normal, which is fast

[Super]

Hello LittleEngines and Welcome to Blue Plastic Tracks.

Would need a little more information... Do you hear the motor running or does it go in and out? When the motor is running and you place your finger on the rear, drive, wheels, do they stop spinning even though the motor is still running? Do you see a lot of hair wrapped around the axle?

What do you mean by "middle wheel" might be your problem?  Might you be able to give us a video or at least some pictures?