When Starsky and Hutch meet Huggie Bear in the alley, a cellular phone tower can be seen in the distance. Cellular phone towers did not exist in the 1970s. The FCC authorized commercial cellular service for the USA in 1982.
When Starsky visits Willis in the hospital, the boy is watching The Jeffersons (1975) on TV in the daytime. The movie is set in 1975 according to its own internal evidence (Huggy Bear has an advance model of a 1976 car that's due to go on the market "next year"), the same year the series began its run; it couldn't have been on in the afternoons at that point in time.
When Hutch wakes up in bed with the girl, he walks out past a very nice fish tank, with several fish - including a Blood Parrot Cichlid, a hybrid fish bred specifically for its color and distinctive, unusual (and unhealthy for the fish) shape, in 1986.
When Starsky and Hutch (and the Torino) get shot at by the Korean gunman, you can hear the cartridges from Starsky's semi-automatic pistol hit the ground as they are ejected. When Hutch fires his revolver you hear the same sound. A revolver retains cartridges in its cylinder when fired.
During his speech, Reese Feldman attributes "To err is human, to forgive divine" to William Shakespeare. Huggy Bear credits the same line to God (presumably meaning the Bible). In fact, this line was written by Alexander Pope, in his "An Essay on Criticism" in the early 1700s.
When Starsky and Hutch (and the Torino) get shot at by the Korean gunman, Hutch frantically grabs the radio mike and calls in the license plate number of the gunman's car, then hurriedly throws the mike into the Torino and pursues the gunman. Moments later, after the gunman escapes, the dispatcher radios back with the license info and we see the radio with the mike neatly hung up on the clip.
When Reese's boat is leaving Starsky and Hutch in its wake near the end of the movie, the rear entrance is on the left rear side. On the next shot with him and Kitty the entrance has moved to the right rear side.
When Hutch tackles Starsky at the end of the disco dance-off, Starsky's wallet is lying on the ground over his left shoulder. When Hutch picks up the wallet, he picks it up over Starsky's right shoulder. After he tells the crowd that he is a cop, he is still holding Starky's wallet in his hand. In the next shot, the wallet is lying on the ground, over Starsky's left shoulder.
When they are in the bar, Starsky and Hutch mistake Jeff for Big Earl. Jeff then shows them his shirt, which has his name Jeff sewed into it. When Starsky grabs the shirt, in the close up he grabs it with his left hand, but in the next shot he has the shirt in his right hand.
When Hutch takes the money out of the "Floater's" wallet, it is completely soaked. A short time later, Starsky & Hutch are examining other paper items out of the wallet, yet they are completely dry, and appear as though they have never been wet.
When Starsky & Hutch start out of the marina parking lot before they attempt to land the Torino on the boat, you see a couple of big, black dirty areas behind the front and rear tires on the fender and quarter panel. In the shot immediately following, the black is gone and the Torino is now completely clean.
In the beginning shots, when Starsky is chasing the purse snatcher, he is wearing blue and white shoes. When he jumps onto the Cadillac's convertible top, his stunt double is wearing brown or black shoes.
While being shot at by the Korean, Hutch calls in the plate on the radio while outside the passenger door then throws the mic into the car on the seat. Then when receiving information on the radio the mic is hanging by the bracket aside the radio.
When Starsky is running on the beach he falls and his headphones fall from his head. The batteries fly out of the headphones and land on the sand, yet they still work when Starsky puts the headphones back on.
In the locker room, when Hutch pulls Starsky off of Manetti, his hands are on top of Starsky's shoulders. While Manetti is talking the shot changes angle, and Hutch's hands are suddenly down by Starsky's elbows.
During the chase scenes Starsky drifts the Torino around the island of the parking lot but is stopped by the ice cream truck. The camera on the passenger side of the truck shows the car sliding right with the wheels pointed to the right, a second later you see the same as the Torino nose dives to a stop from another camera angle. But the next shot the Torino nose dives with the wheels pointed to the left.
Sniffer dogs detect trace amounts of drugs that get into the air and stick to objects that have been near or in contact with drugs. If cocaine was chemically altered to "smell" differently in order to avoid sniffer dog detection, the drug would no longer be cocaine.
Kevin tells the coke dealers that the German Shepherd can "detect smells that even the most advanced technology in the world cannot." With that in mind, we see the fat coke dealer smoking a cigarette who is sitting closer to the dog than the man with the "old coke" (the one that the dog attacks) thus, the dog should have caught the man with the cigarette first.
In the opening of the film, Starsky is chasing the perp in his Torino with the magnetic police light attached to the roof. The light is attached over the passenger side of the car, far out of Starsky's reach since he was driving alone.
In a scene where we see a gun scope aimed at one of the leads, the bullet is fired while aimed towards the drivers window of the car, with the windscreen also in the path of the bullet. But only the side window gets broken.
(at around 1h 30 mins) When the Torino lands you can see the white paint stripe reveal just how much the front of the car is deformed in these jumps. The owner would never do this for fun as it would ruin the car each time.
During the closing scene with the original Starsky and Hutch (1975) actors, Starsky is told about popping the clutch and jumping from 2nd to 4th gear. But, during the jump onto the boat you can clearly see that the Gran Torino has an automatic gear box due to the fact it has no clutch pedal. Just a gas pedal and large brake pedal.