Has the 2.5 when you look up 04 sentras on drop down boxes it has 1.8, se-r ,and se-r spec v . Either way it has the 2.5 and pretty fast.

Maybe it is just called the 2.5s

Supposedly title says SE-R on it

Sentra 2.5 S gets the bigger engine found in the sports models. Here, the 2.5-liter engine puts out 165 horsepower and 175 pounds-feet of torque for quicker acceleration performance. It comes standard with an automatic transmission, four-wheel disc brakes with ABS, and side airbags. A Power Sunroof Package ($700) is available for 1.8 S and 2.5 S