Junior Diaz's first goal in a Mainz shirt and an Adam Szalai effort gave Mainz a two-goal lead before the interval.
Wolfsburg were unable to recover in the second half, wasting chance after chance as their curse at home, where they have not won all season continued.
Two goals in five second-half minutes from Alexander Meier maintained Eintracht Frankfurt's unbeaten start to the season and gave them a 2-1 victory over Freiburg at the Waldstadion.
Max Kruse gave the visitors a shock lead in the 50th minute after Christian Streich's side had spent much of the game defending.
Meier had a goal ruled out for offside, but there was no doubt over his third and fourth goals of the season, which earned the home side a fifth win in six games.
Karim Guede made matters worse for the visitors when he was given his marching orders in stoppage time.
On Saturday, Bayern Munich left it late to to win 2-0 and continue their perfect start to the season with a sixth straight Bundesliga win at Werder Bremen.
Luiz Gustavo and Mario Mandzukic both scored in the last 10 minutes as the Bavarians extended their lead at the top of the table with an eighth triumph in as many competitive games this season.
Although Bremen had matched Jupp Heynckes' side for much of the game, their late collapse cost them dearly as they slumped 11 points behind their opponents.
Defending champions Borussia Dortmund moved up into third - seven points adrift of Bayern - after thumping Borussia Monchengladbach 5-0.
Marco Reus haunted his former side with two goals and an assist as Dortmund bounced back into form.
The Gladbach old boy opened the scoring in the 35th minute and Neven Subotic gave the defending champions a two-goal cushion at the interval. Reus added Dortmund's third in the 70th minute before setting up Ilkay Gundogan for the fourth nine minutes later, while Jakub Blaszczykowski added a fifth.
Hamburg rode their luck to end the week with seven points from three games thanks to a tight 1-0 win over northern Germany rivals Hannover.
The home side managed only two shots on goal over the 90 minutes but one of them, from Artjoms Rudnevs, landed in the back of the net in the 20th minute.
Hannover wasted a hatful of chances and left the HSV-Arena puzzled and empty-handed.
Two goals from substitute Sidney Sam earned Bayer Leverkusen a 2-0 success against Greuther Furth, who slipped into the bottom two after their first away defeat of the season.
After a tight first half, Sam sprang from the bench to fire Leverkusen ahead in the 50th minute. He then scored the second in the 62nd minute to give Leverkusen only their third win of the season and lift them up to sixth.
Stuttgart picked up a much-wanted away 2-0 victory over Nuremberg to lift the pressure on coach Bruno Labbadia.
Vedad Ibisevic gave the visitors the lead with the quickest goal in the Bundesliga this season before Martin Harnik wrapped up the win in the 75th minute.
Stuttgart's players celebrated with their coach after claiming their first win of the season while consigning Nuremberg to a third successive defeat.
Hoffenheim and Augsburg struggled to focus on playing football in a game which ended goalless at the Rhein-Neckar Arena.
Playing just 24 hours after a car crash left Hoffenheim midfielder Boris Vukcevic in a coma in hospital, neither side managed to create any major chances to win the points as thoughts were clearly elsewhere.
An moment of madness then cost Sejad Salihovic a red card in the 88th minute of an otherwise tame stalemate.
Sunday's Bundesliga Results
Saturday's Bundesliga Results
Friday's Bundesliga Result