The trio all qualified for the last World Cup in Brazil in 2014, with Costa Rica making the last eight and Mexico and the United States going out in the second round.
Jurgen Klinsmann's American team suffered a shock early goal from their Caribbean opponents with St Vincent striker Oalex Anderson opening the scoring in the fifth minute when he cut in from the left and curled a right foot effort past keeper Brad Guzan.
But goals from Bobby Wood (11) and Fabian Johnson (29) put the United States on their way to a comfortable Group C victory in St Louis.
Two goals from Jozy Altidore (31, 74), a Geoff Cameron header (51) and a Gyasi Zardes (58) strike made sure of a winning start for the U.S. who have not missed out on the World Cup since 1986.
Mexico's new Colombian coach Juan Carlos Osorio made a winning start to his stint in charge of El Tri at the Azteca Stadium.
Andres Guardado calmed early nerves with a beautiful, curling free-kick into the top corner in the seventh minute of the Group A clash.
Hector Herrera was credited with the second goal in the 42nd minute when he floated in a dangerous ball which made its way into the far corner with Javier Hernandez's attempt to flick it home distracting El Salvador keeper Henry Hernandez.
Striker Carlos Vela completed the win after the break with a delicate chip over the advancing Hernandez.
Costa Rica are favourites to top Group B but they faced determined opposition in San Jose against a much-improved Haiti.
Cristian Gamboa slotted in the 29th minute winner after a superb passing move from the Ticos, who in Brazil managed to qualify ahead of Italy and England in their group.
In Group B's other game, Panama enjoyed an impressive 2-0 win in Kingston against 2015 CONCACAF Gold Cup runners-up Jamaica.
Panama, who missed out on a place in Brazil on the final day of qualifying last time round, made sure of three points with goals from Armando Cooper (43) and Alberto Quintero (52).
Trinidad and Tobago, who have not made the World Cup since their appearance in Germany in 2006, got off to a positive start in Group C with a hard-earned 2-1 win in Guatemala.
Khaleem Hyland's long range strike (67) and a superb Kenwyne Jones volley (80) gave Stephen Hart's team a two goal cushion before substitute Carlo Mejia's last minute consolation goal.
Canada edged Honduras 1-0 in the late Group A game on Friday after Will Johnson's first half goal in Vancouver.
(Reporting By Simon Evans. Editing by Patrick Johnston)
