In the opening hostage scene, Roper is wearing an orange v-neck sweater with a t-shirt showing under it. The t-shirt disappears and reappears multiple times.
The stripes on the knot of Sam's tie, change multiple times before he meets up with Korda in the the elevator.
When Earl holds the gun to Debbie's head, the hammer goes from cocked to uncocked and back again between shots.
When Roper knocks on Veronica's door to visit Troy he is completely dry, even tho it's pouring rain outside when he arrives.
The car that overturns in front of the cable car changes to a different make, with a different license plate.
When Michael Korda opens the door to get into Roper's truck, he is carrying a coat on his arm. In the next shot, a coat is on the hood of the truck. It's Roper's coat.
When Scott tells his superior that Kevin won't last two weeks his head is turned away from Kevin so there's no way that Kevin could have read his lips and known that he said that.
The trolley hits a car near the end of the movie. When the car flips over, there is no transmission or drive shaft underneath.
When the cable car pushes the Cadillac, the Cadillac is clearly suspended several inches off of the ground, yet the tires smoke as if it was on the ground.
The cable car, when speeding uncontrollably, clearly runs to the right of the tracks for a split second.
During the trolley car chase scene, one passenger is holding a fake dog.
When Roper visits Korda in jail, Korda's voice doesn't match his mouth movements.
During the cable car chase, when McCall swerves to avoid the red car that flipped over, a camera is visible on the right side of the road, next to the sidewalk.
As the red Thunderbird is hit by the cable car and flips over another car you can see smoke under the center of the car; from the explosion (possible hydraulics?) that caused it to flip as it's going over.
After the car flips, an SFPD officer is clearly visible on the intersection, downhill from the cable car to the left of the screen.
The last scene is supposed to be set on Tahiti, but the final shot is on Bora Bora, another island in French Polynesia (Tahiti is the best-known). Tahiti doesn't have any white beaches with palm trees around a blue lagoon.
The final scene with Korda is not Mare Island. No dry docks and the buildings were brick not metal.
When Korda says to enter Mare Island through the North gate of Dixon he's wrong. The North gate is off Sears Point Road. The tower that says Mare Island is from the drawbridge on the causeway which would be the main gate.