after i replaced the headers and exhaust on my miata i was driving home and the car shut off and turned back on right away.. drove home fine. parked it for the night and in the morning the car would crank but it wouldnt start. i took out my spark plug to check if i was getting spark and no spark what so ever. i changed the coil pack and my spark plugs as of now. and no spark.. any ideas?

i checked- fuses- main relay fuse-

no spark at all..

 

bump. can anyone help me.

 

Cam sensor.

 

First, I would look around the exhaust header for burned/disconnected wires, since you were just working there.
I just had this problem with one of my Miatas and it turned out to be a faulty main relay, but it could be a number of things along the power line (main fuse, ignition switch).
If you have a volt meter, pull your CAS plug and check for +12v. I think the plug goes; Ground, +12v, +5v, +5v. If there isn't 12v there (with the switch on) let us know and I'll help trace it down. The 12v wire is white with a red stripe.