My pulsar coughing when over 2000 rpms
So I own a 98 Nissan pulsar n15 1.6L. So the other day drive home from work I went to take off and I put accelerator to the floor and I lost speed in my car. If I drive it with out putting my foot down it will drive fine. But as soon as the revs good over 2000 rpms in wants to cough and carry on and I thought it might of been ignition coil so I brought a new one and replaced it and it is still doing it. I need help as I need my car to get to work thanks for take time to read and helping me out .