1996 Nissan Sentra check engine light

Bad spark plugs can cause your check engine light to come on but don't just blindly replace parts hoping that it will fix the problem. If you dont own a scanner, then go to a local Autozone, they will scan your car for free and tell you what codes come up. If a misfire code comes up then it may be the spark plugs. But it could also be some other ignition problem. Refer to this video for testing the ignition system: https://www.2carpros.com/car_repair_video/test_engine_ignition_system.htm

The misfire code will tell you which cylinders misfired. Check for spark in those cylinders using the method in the video. If you've got spark to those cylinders then replace the plugs in the misfiring cylinders, or just replace all the plugs if you want to be thorough. If you've got no spark then you've probably got a weak distributor point or a worn out plug wire. in that case just go ahead and perfom a full tune up: spark plugs, wires, distributor cap & rotor