Episode #2.2 - S2-E2
Continuity mistake: During the scene between Hunt and Tyler, which takes place directly after Hunt has been "communicating" his outrage to Dickie Fingers, by hitting Dickie's hand repeatedly with a telephone, Hunt puts his hands in his pockets. However, in the next shot, which is the opposite camera angle, Hunt's hands are suddenly back out of his pockets. When the camera angle changes again, they're back in, all with no movement on Gene Hunt's part.
Episode #2.2 - S2-E2
Continuity mistake: Look out for the self-cleaning windscreen on the car driven by D.C. Skelton. As it turns into the field, it's dirty one moment and clean the next.
Episode #2.3 - S2-E3
Factual error: Sam and Gene arrive at a construction site to investigate stolen explosives. There is a green first generation Range Rover parked on the site. The Range Rover has its driver side (right side) side view mirror mounted on the door. In 1973 Range Rovers had side view mirrors mounted on the front end of the front wing (fender), not the door. The mirror was not mounted to the door until after 1978. (00:08:58)
Episode #2.4 - S2-E4
Continuity mistake: When Sam sits down next to Carol Twilling on the bed, asking, "Do things ever get a bit frisky?" the top button of his shirt is undone. The camera cuts away and back, only to find that there are now miraculously two buttons undone, not just one. Sam has not moved in this time.
Episode #2.6 - S2-E6
Factual error: In the back of the record shop amongst the audio equipment you can see 2 A&R Cambridge A60 amplifiers. These were not available until 1977.
Suggested correction: The show is set in a form of purgatory in 2006. It's not really set in 1973.
Episode #2.8 - S2-E8
Factual error: The silver Ford Granada seen in the final episode is a Ghia model, which was not made until 1975.