90 240sx electrical problem

[drivinsidewayz86]

hi i have a 90 240sx that has a 93 ka24de swap and it ran for a while then developed a electrical problem i have taken the hole car apart to check and still yet to find the problem the diagnosis is start the car

it hesitates to idle and eventually smooths out then with all the accessories off the car runs fine once i turn the headlights on the car starts to lose power

i checked the relays in the driver kick panel to see what they were reading and there 12volt input on the relays where reading 9.65 volts but the alternator is puting out 13 volts if any one has any suggestions that would be great

[drivinsidewayz86]

well i fix it

the problem bad ground for harness in back of drivers headlight