Continuity mistake: The green Alfa in the opening minutes has its side, and mirror, wiped out by a lorry. For the next 5 minutes it then drives around in perfect condition. (00:05:43)
Continuity mistake: In the final battle, Wasp and Ant-Man are in the van trying to get the quantum tunnel operational. We cut back to the fight and we can see Ant-Man there too, fighting in his giant form. (02:22:20 - 02:23:00)
Continuity mistake: After the speeder chase, everyone lands in quicksand. In one shot, 3PO is buried headfirst. In the next, he has flipped and his upper body is visible.
Factual error: At the end of the movie, a Willys is shown with an inscription on the back: "Left hand drive vehicle." The scene takes place in Midway or Pearl Harbour. This inscription on the vehicle was only for the US forces in England beginning in 1944.
Factual error: The space shuttle is spinning due to a stuck thruster. In such a case, the spin would be continually increasing as there is no air resistance. The X-Men shoot out of the thruster and the spin stops. Not factual. They would have needed opposite thrusters to stop it. (00:11:55)
Plot hole: Sarah turns up on the bridge to fight the Rev-9, we later learn that she is texted the location of where to be as when the terminators travel though time it causes a gravitational anomaly, and this is where she needs to be. The Rev-9 had been there ages killing Dani's dad etc, Sarah would have no idea to be on the bridge after the terminator has chased them though the town - she can't possibly know that location.
Factual error: During Lee Iacocca's slide presentation to Henry Ford II in 1963, there are two slides that reference James Bond. One shows him standing next to the Aston Martin DB5, which made its debut in "Goldfinger" in 1964, and another shows a still image from "Thunderball", which was released in 1965.
Other mistake: Vic and Stu get into a shoot out inside the animal hospital with some thugs, guns firing all over the place. The building is full of animals like dogs and cats and parrots. However, the animals stay completely calm and quiet during the entire gun fight and seem unaffected by the rapid, very loud banging of gun fire. Even right after it, a cat that just had it's tail stepped on sits on a dead body and meows like nothing happened. This is completely uncharacteristic of how animals would act to loud gunfire in an enclosed building, especially in a vet's. (00:45:00)
Continuity mistake: When Peter and MJ hug on Tower Bridge he gets some blood from his face onto the left shoulder of her jacket. From other angles there's no blood.
Other mistake: During the restaurant shoot out between Jr and the bad guys, he takes Sasha's weapon (Kel-Tec P-3AT) and opens fire on the bad guys. The Kel-Tec P-3AT is chambered in .380 and holds 6+1 rounds. During the firefight, Jr fires 9 times. We also see the bottom of a spent casing and it shows .22. (01:12:00 - 01:13:00)