so heres the issue, 97 civic b series swap no codes or history codes. aftermarket radio no subs or seperate amps. ok so what happens is it will start up fine and show 13.9 or 14.1 volts, after warming it up and driving out for about a min ill pull to a intersection and notice my voltage at 12.2v! once i accelerate and engine speed reaches about 3500 or so it will go back up to 13.9v. at low speeds it will bounce up and down between shifts if engine speed is around 3500 or lower. the odd thing is if i turn on the running lights or headlights and use the rear defroster, it will go up and stay up. this tells me the system is capable of producing the need voltage but isnt doing it all the time. i replaced the alt. still does it. i went thru all my wireing that is aftermarket or repaired for any prob. but found nothing. battery is getting old but test fine under load testing. im stumped so i need some ideas!

 

did you check the alt reg.?

 

first check for belt tension and make sure it isnt slipping, then have the alternator load tested.....Im sure it needs replaced/rebuilt....I have a small shop down the street from me called "the electric garage" that will repair alt and starters. I have never had a single issue from his stuff....unlike the chinese crap you buy from a parts store that shows up DOA half the time......Have it rebuilt rather than replaced if you can find a shop that does that kind of work around you, plus its usually cheaper

 

yeah ill look into that. it is the second alt. ive put in but the one i got in now was from a guy second hand.... did run fine tho in his car( i helped take it out) has anyone heard of a voltage stabilizer under the fuse box in the engine compartment? i heard about it but have no idea if its for real. im gonna get a new battery from work and pop it in, if it doesnt fix it at least i can put it back on the rack!

 

alt. , battery and all wires connecting charging system test fine. gonna order a new alt. and swap it to see, does anyone know of a voltage stabilizer on a honda? ive heard about it but dont know for sure where it is.