Factual error: Right after the movie title is shown, you can see in the background a UPS truck. The only problem is that it has the new logo on the side of it. (00:02:00 - 00:06:00)
Factual error: As Starsky and Hutch are driving back from their "interrogation" of Big Earl, they are listening to the Starland Vocal Band's "Afternoon Delight" on the radio. However, the film is set in 1975, and the song was not released until 1976. (00:38:00)
Factual error: When Starsky and Hutch are chasing Reese, there's a shot of a very modern yacht in the harbor (definitely not from the 70s). It's in the shot where the Gran Torino is doing a skidding right turn into the harbor, right above the car. (01:26:30)
Factual error: In the beginning of the movie, before Starsky jumps their Grand Torino, they are coming out of the police station, and there are police cars out front. But the police cars are 1980 Pontiac Bonnevilles, which is impossible considering the fact that the movie is set in the 70's. (00:16:15)
Factual error: When Starsky is coked up, you see him on numerous occasions snorting and rubbing his nostrils (sign of classic coke abuse - done to clear the nose and sinus). As he drunk the coke in coffee, he wouldn't be doing this. (00:45:05)
Factual error: At the end of the film, when Starsky gets the Ford Gran Torino from the original Starsky, he says something about "not jumping the clutch." The car in the film has an automatic transmission, hence no clutch. (00:54:15 - 01:33:05)
Factual error: Starsky uses a .45 with night sights on it (for the non-gun people: they glow in the dark). In the 70's they weren't invented yet.
Factual error: The events of this film take place in June, 1974. But at one point, the boys shoot out the rear window of a 1978-80 AMC Pacer which won't be built until the fall of 1977. While Huggy's '76 Lincoln is also not possible, it's an obvious joke suggesting he has good connections. The Pacer, however, is a clear mistake, as nobody has connections good enough to have a car over three years before it is built. (00:53:25)
Factual error: At the disco, the DJ describes a dance move which only came out in the 80's. The movie is set in the 70's.
Factual error: In the bot mitzvah scene, the microphone that Vince Vaughan's character is using is a shure beta 58. The movie is set in 1974, but the mic wasn't made until 1989. (01:02:30)
Chosen answer: It's from Adam Sandler's film - The Wedding Singer.