Dirk Kuyt opened the scoring for Ersun Yanal's men in the 17th minute before Moussa Sow and Pierre Webo made sure of the points with second-half goals.
Fener's lead at the summit is looking insurmountable after title rivals Galatasaray and Besiktas both suffered slip-ups this weekend.
Champions Gala were held to a 0-0 draw at Konyaspor on Saturday, while Besiktas fell to a dramatic 1-0 defeat at Karabukspor 24 hours earlier.
A 90th-minute strike from Nigerian attacker Michael Eneramo handed the points to the hosts as Besiktas were dealt their first defeat in five league matches.
John Utaka scored a double to help Sivasspor move up to fourth with a 3-2 home triumph over Gaziantepspor.
The former Montpellier man netted his second and the winning goal in the second minute of injury time after Marek Sapara had seemingly earned a point for the visitors with an 86th minute strike.
That win leapfrogged Sivasspor above Trabzonspor following their 0-0 draw at Elazigspor.
Kasimpasa also took advantage of Trabzonspor's setback, surging up to fifth place with a comfortable 3-0 victory against Kayseri Erciyesspor.
At the other end of the table, a Mert Nobre brace gave bottom club Kayserispor a third straight win as they beat fellow strugglers Antalyaspor 3-1.
Elsewhere, Rizespor boosted their survival hopes with a 3-2 win at Akhisar Belediyespor and Genclerbirligi claimed a 1-0 success over Eskisehirspor.
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