not getting fire, change distriber cap and rotor, crankshaft sensor, fuses ok

how do you check it and where is it

The coil is in the distributor , unfortunately , I don't have enough info on that brand to tell you exactly how to test it. Take the cap and rotor off again and look (don't touch) and see if there are any rusty looking trails any where. IF the black cover comes off easily that may give you a better idea of what is going on (signs of arcing) Next , since I don't have info , and checking for parts on-line doesn't show a separate coil , maybe call NISSAN dealer and see if it's a 'dealer only' item , or if it only comes with the distributor as an assembly. What I found on-line(autozone.com) was either a partial dist. or one complete with cap and rotor and that one said coil was included. Sorry I'm not up to par on Nissan.....good luck , reply if you have more questions if you do pull it back apart.