car dies.....help

[fuzzydice]

i just put in my pbm coilovers into my s13 and suddenly my car/battery will die while driving. my brother had this problem on his s13 and we never found the cure... i rubbed into 2 wires in my front left fender due to me putting it to low but i fixed those and it hasnt changed.... i tested the load (12.9v while the car is off) (12.3v while running) i dont think it is the alternator because when this happend to my brother i swapped him alternators and it worked fine on my car but his car still had the same problem.... any advice as to where i should start would be great

[Mountain_Man]

if im not mistaken you should have more voltage when its running. it sounds like an alternator to me. but before you do that just check the alternator fuse.

[fuzzydice]

i did check it and its fine.. im just going to take it to a mech to find out what it is and ill just fix it

[mxexux]

Alternator should definitely be charging the battery at more than 12.3v. With the car on, the battery voltage should be ~13.5v. Take the alternator to your local autoparts store to check it for free. Or you can start checking the charging cables for high resistance. Also, another trick to checking the alternator: turn the car on and measure the battery under AC voltage on the DVM. If its higher than 0.5VAC then the regulator/rectifier on the alternator is bad.

[REALIZE.]

ever check if u have any exposed wires? sometimes they will ground together.