Rueda marks Ecuador debut with win
Rueda, who steered Honduras to this year's World Cup, was appointed last month to replace Sixto Vizuete, sacked after Ecuador failed to reach the finals in South Africa.
Striker Cristian Benitez put Ecuador in front after just 30 seconds of the match at the new Omnilife stadium in Guadalajara with a powerful shot after beating several defenders inside the box.
Mexico equalised when Ecuador centre back Luis Armando Checa turned the ball into his own net trying to clear a cross from striker Javier Hernandez four minutes before half-time.
Forward Jaime Ayovi combined well with winger Antonio Valencia before scoring the winner just before the hour with a right footed shot.
Ecuador have another friendly away to Venezuela on Tuesday when Mexico are at home against Colombia in Monterrey.