i have a 90 civic si that i swapped a 90 ls motor into.. i had the whole wire harness apart so i could re loom it. i put the motor in the car and got it all hooked up all the grounds secure, cranks over great, but no spark. so i tested the coil when the distributor was in the car and it measured 4 volts? i pulled out the distributor and tested the coil and it measured 14 volts? put it back in the car and right back to 4 volts.. am i crazy or what is going on?? i thought grounding out on something but what could be grounding out in the head and distributor? if any one has had similar problems or some suggestions to help me out with that would be great... thanks for the help.. also if you wanted to email me my email address is skaterjason55@hotmail.com
thanks again

 

have you checked the cap and rotor?

 

yea i checked the cap and rotor and coil and i tryed 2 different distributors, 2 different ecus and even bought a brand new main fuse relay from honda!! damn this sucks!!

 

im sure you checked this already but...you have the 3 grounds right? thermostat is the one i missed...no codes at all?