look on the back of the car, on the trunk lid. on the drivers side, you will see the word "SENTRA" in gray letters. in the middle, you'll see a nissan emblem. :thumbup: on the passengers side, you will see the model - SE, XE, E, Limited Edition, SE-R, etc. if there's no model, it's probably a bottom-of-the-line model that came standard with 4 tires and a heater. nissan played with the sentra's features for a few years.
unless it's an SE-R, you will have the GA16DE. it's still a powerful little motor.
no, I've owned several nissans. an 89 sentra I wrecked, an 88 maxima I traded in, now I have 2 94 sentras and I recently acquired an 88 sentra. I loved the VG30E engine in the second generation maximas but one of my 94 sentras is a 5-speed and with a good tuneup it's rather impressive for a 4-cylinder engine. even my other one, which is an automatic with 212,000 miles, still accelerates like it's young.