Factual error: In the opening scene, the ambulance takes Rocky to Pennsylvania Hospital, whose ER is between 8th and 9th Streets, on Spruce. The ambulance is shown turning off Broad, onto Market Street, then back to 8th, and then down 8th to Spruce (presumably) to get to the hospital, when it could have just made a right at Lombard or Locust. (00:01:59 - 00:04:01)
Factual error: During the period in which Apollo is trying to bait Rocky into a rematch, Rocky puts the TV on and sees a sports report in which Brent Musburger announces that the Los Angeles Rams defeated the Tampa Bay Buccaneers on a late field goal by Frank Corral. The movie takes late 1976-ish. The Rams did not play the Buccaneers in 1976, and Frank Corral did not join the Rams until 1978. The game in question occurred during the 1978 season.
Factual error: Even though the story is supposed to take place in late 1976-ish, the Trans Am that Rocky drives is a 1978 model.
Factual error: Rocky buys and drives a Trans Am. Later, we find out that he can't read after his commercial goes horribly wrong. He couldn't have a driver's license because he would need to pass the written test first. You can't take the test if you can't read the questions or the driver's manual for that matter.
Suggested correction: It's not that he can't read at all, he just reads slow and has some trouble. It may or may not be enough to hamper him from taking the test. But is it ever established that he has a driver's license? He wouldn't be the first person in Philadelphia to drive without a license.
When you can't tell the difference between simple words like rat and cat, there's a pretty good chance you can't pass a written driver's test, which is why I said he "couldn't" have a license.
