1987 civic hatch with 1.6L DOHC jdm zc swap was running fine started surging when running about 4 grand in 5th gear and wanted to stall when i pushed in the clutch and glide, then it ran fine and got down a little farther and started it again and then just died and then nothing, has spark, i have an 8 gallon fuel cell and an in-line fuel pump but i have never had a problem until now, just flip the switch and go. im thinking its electrical but i dont know where to start?