Okay I have a Honda Civic 91 and I just did a LS swap in my car! At first my car would not start here or there before! But now it's not starting at all now! When I try to start the car it'll crank like it's about to start then it'll just die! The battery is still good cause I just charged it and even try jump starting it! And we did some test on the fuel pump and its winding! As for the main relay, it clicks when trying to start! So I don't know what to do next? What do you guys think it is!

Thanks,
Eddie

Check your ground connection

Test/replace the ignitor and coil.

Oh okay I'll try that asap! And what are the other possibilities that could be wrong with my car besides checking the grounds and test/replace the ignitor and coil? I really appreciate it! Thanks!

If the CEL comes on and goes off after 2 seconds, when the ignition switch is turned to ON, then focus on 1) ignitor and coil and 2) distributor housing. Ensure that during the 2 second interval that you can hear the fuel pump run and the main relay click.