Factual error: In the scene where Shaw is talking to a goon while fixing his car he states the simplest things cause the most problems while holding a spark plug. We know this can't be right as Brian concludes the car is a turbo diesel like a Le Mans car, which would actually use a glow plug and not a spark plug. (00:19:50)
Factual error: Hobbs would not be able to walk around London with a holstered gun on show, despite his position in the USA.
Suggested correction: We've learned to know from the movies that he isn't the type to respect and follow all rules, especially not when they're in his way to get to his goal.
British police would not allow him to carry the weapon. End of.
Factual error: The runway action sequence is 13 minutes. Allowing for some events happening simultaneously, different angles, etc., it's about 9 minutes of "real" time. Given the speeds on the runway are high enough for the plane to take off / land (~120mph at the very minimum), that makes the runway about 18 miles long, not remotely feasible. Even half that length would be too much by far. The longest runway in the world is much less than 4 miles.
Factual error: Brian mentions that the engines in Shaw's flipcars sound like the engines you hear at Le Mans, turbo diesels. These cars have over 500 horsepower and are capable of reaching speeds upwards of 250 miles an hour. They also weigh less than one ton. Shaw's cars seem to meet all these demands: massive power and torque, no body fat and very fast. But here is also a problem: Dom is easily able to keep up in a factory-tuned BMW, which would be nearly twice as heavy, and Hobbs is able to keep up in his "four-wheeled tank", which would be thrice the weight, with even less power. There is no way that an extremely good driver like Shaw wouldn't be able to lose them with such an advantage in terms of power to weight ratios.
Factual error: When Mia changes gear to pull the Antonov down, she moves the gear lever straight down, then straight up again, meaning she would end up in the same gear.
Factual error: When the Mercedes jeep hits the wall at the end of the plane, Shaw goes straight through the windshield and falls to his death in a cloud of shards. Windshields on modern cars, like that jeep, are made out of laminated glass, layers of glass and plastic, precisely designed to prevent shattering into those deadly daggers during an accident and kill the unlucky guy in front of it.
Factual error: There is no way that a 1 ton car suspended from a wire loosely twisted around the barrel would stop a 70 ton tank going at least 60 miles an hour dead in its tracks, let alone flip it end over nose.
Factual error: In the scene of Paul Walker getting off a plane in an orange prison jumpsuit escorted by U. S. Marshals, the jackets worn by the Marshals have the misspelling "Marshall" printed on them. (00:56:45)
Factual error: The range rover has a UK 'PE60 EKJ' number plate indicating it's a late 2010 car. It's a 2002-2005 model. (00:48:00)
Factual error: None of the cargo on the plane at the end is strapped down - the cars and crates, boxes etc in the middle of the cargo hold. The plane would not even taxi like that, let alone take off.
Factual error: The route Dom and Letty use for their race is not consistent with the sights shown in the background - they are jumping all around the west end of London, then pull up near Battersea Power Station which is south of the Thames.
Factual error: Roman is searching through the shot-down vending machine after the massive chase. Two of the products shown in the machine are a couple of Nestle 100 Grand bars and a couple of Nestle Butterfingers bars. This scene takes place in the UK - 100 Grand bars and Butterfingers bars aren't available in vending machines in the UK, just specialist sweet shops. (00:34:10)
Factual error: After Letty and Riley fall down the stairs in the tube station, Letty jumps onto an unpainted train that has a Northern Line map inside. The London Underground hadn't had an unpainted train in service for almost ten years when the movie was released, and the train is also the wrong style for the Northern Line.
Suggested correction: That's exactly the problem that Shaw is referring to, a member of his team installed the incorrect plug which caused a problem, i.e. a Spark Plug and not a Glow Plug (a simple thing, causing the problem), along with the 'good' being simple minded and causing the rest of Shaw's team a problem.
The glow plug isn't what causes combustion in a diesel like how a sparkplug does for gas. The wiring harness for a spark plug vs a glow plug is completely different and they aren't interchangeable. You can't just accidentally put a spark plug in a diesel, it doesn't work like that.