Factual error: As a trash compactor Wall-E does not function logically. When he fills his chest compartment with garbage and runs his internal compactor, the cube that exits his body is the same volume as the trash he puts in, despite that trash having been compacted. He does not add extra trash to fill the empty space after running the compactor - there are three scenes that show him filling up only once with loose garbage and then ejecting a densely compacted cube. (00:02:30)
Suggested correction: You haven't noticed the exact shape of his body. The back sticks out a tad. Garbage fills the space and the back pushes in to compress it.
Factual error: When AUTO tilts the Axiom during the argument with the captain, which later results in WALL-E being crushed and everyone sliding to one side, should not be possible. In space, there is no gravity, and on the Axiom there is artificial gravity, meaning everything is pulled inward, so if the ship turns, they shouldn't notice and nothing should change.
Factual error: The Rubiks cube that Wall-e pulls out of his cooler is not accurate for a real cube. That cube has white and yellow on the same piece which is impossible for a real cube. Then after Eve solves it, white and yellow are on opposite sides as they should be.