I have a 97 civic hatchback with a japanese B16a2 swapped into it. It has been running fine for about 2 years. Just recently the car dies after it has run for about 20 minutes. Right before it dies the main relay rapidly clicks. After the clicking the car looses power and the CEL comes on. I've changed out the main relay to another known working one and it does the same thing. I have also checked all the grounds and everything is secure. The car gets spark. The fuel pump primes.

 

bump

 

Hmm... thats pretty weird. Did you check all other fuses to see if one blew? Also what did the code read?

Free bump.

 

Usually if the car will not start or the car dies it will always though a fuel injection code.

But check the code and see what it is, I would say its something to do with the iacv . If you ever unplug this, the car will do exactly what your talking about, it will start up cold but once it hits the warm mark it will die.