Nigel Worthington has challenged York to make sure they stay out of the relegation zone as the season comes to a climax.
City climbed out of the drop zone after they ended the best home record in the top four divisions against a Northampton side looking to extend their 10-match winning run at Sixfields.
The relegation battlers beat Northampton 2-0 thanks to Ashley Chambers and an own goal from John Johnson to extend their unbeaten run to four games under Worthington while Cobblers slipped to a third defeat on the bounce to lose ground on the automatic places.
Worthington said: "I don't want it to be a case of after the Lord Mayor's Show. We're on a decent little run now but I told the players straight afterwards that this game has now gone and now we focus on next week's fixture and try to build on this result.
"We've worked hard over the last few games and got our rewards, the players are now enjoying themselves. We beat Plymouth, who were doing very well at home, got a point at Bristol Rovers, who had been on a good run, and now we've won at Northampton, who have the best home record in the league.
"Northampton is a very hard place to come with their home record, we knew we had to perform and the players did just that. Northampton's home form has been exceptional and we knew we had to work hard and play when we could.
"Hard work are only two small words but that's what you need in these sort of games. We played well when we had possession and I think we deserved the victory."