The Argentine gave City the lead five minutes before half-time when he emphatically finished from a tight angle, leaving Reds goalkeeper Alison with no chance of saving.
Aguero had already held the record for his goalscoring antics against Liverpool at Etihad Stadium, but the strike extended his run.
It also furthered his lead as the top goalscorer in matches between the Premier League's top six clubs since the start of the 2011-12 season. Aguero has now scored 37 times against England's elite sides, 16 more than his closest rival Harry Kane.
Aguero also brought up his 250th career league goal with the strike, with 153 of those coming since he moved to the Premier League.
Aguero's goal came after a tight opening to the game, with Liverpool enjoying slightly more possession. The visitors claimed 56 per cent of the ball in the first period but had the same number of shots as their opponents, with each side only managing two efforts on goal.
The game had been highlighted by many as a must-win affair for City, who trailed league-leaders Liverpool by seven points going into the match in Manchester.
A win for the Reds would leave Pep Guardiola's side 10 points behind them and a point off of Tottenham in second.
They did manage to get back to winning ways before the crunch encounter however, wrestling back some sort of momentum with a 3-1 win at Southampton where Aguero also got on the scoresheet.
The 30-year-old's goal against Liverpool took him to 10 for the league campaign, although he still sits four behind Kane and Pierre-Emerick Aubameyang after injury trouble earlier in the season.