Has an NFL team ever won all their home games and lost all their away games?

Close ones were the 1999 Cowboys, who were 7–1 at home and 1–7 on the road, as were the 1992 Broncos, 1989 Raiders, 1981 Lions. The 1971 Chargers were 6–1 home, 0–7 away. 1964 Jets were 5–1-1 home, 0–7 away. 1957 Rams were 5–1, 1–5, as were the 1955 Packers. The next team to get close was the 1929 Boston Bulldogs, 4–1 to 0–3, and the 1925 Canton Bulldogs had the same record. The only teams ever to win all of their home games while losing all away games were the 1923 Akron Pros, who went 1–0 at home and 0–6 on the road, the 1922 Louisville Brecks and 1921 and 1922 Minneapolis Marines who both went 1–0, 0–3, 1921 Rochester Jeffersons were 2–0, 0–3

So the answer is, it has happened, but not since the NFL was a real league. In the 1920’s the NFL was in its infancy, and some clubs did not play full seasons, and it was not uncommon for a club to only play one game never to play again.

Some interesting observations though, It is quite common for teams to go 4–4, 4–4, and there were some teams which showed an opposite of home field advantage, going 2–6, 6–2.