City slipped five points behind leaders Liverpool in midweek, after losing 2-1 to Newcastle.
Guardiola’s men host Arsenal on Sunday, knowing victory will take them within two points of Liverpool and keep the pressure on Jurgen Klopp’s side, who travel to West Ham on Monday.
“It doesn’t matter, if we are five, six, seven or eight points behind, we have to improve our game.
“That’s the issue.
“We have to improve our game. Regarding the last game, that’s what we have to focus on.
“We are not happy about the last performance. Everyone knew at half-time and at the end of the game.
“But if we didn’t have motivation, then we wouldn’t be here. We want to sustain the top level.
“The team know our principles and how to improve – simple things, a few things. Against Newcastle, we didn’t create or do something different,” Guardiola told a press conference on Friday.
After facing the Gunners, City travel to Everton on Wednesday, before hosting Chelsea at the Etihad Stadium four days later.