Electrical Problem + Running Rough

[ChuckNorris]

So i think its related...

When i turn on the car none of the gauges or power options work at all until i rev the car over like 1500 rpms... its also running really rough and I took it for a drive and when u get past like quarter pedal or give it any kinda gas around 3000 it sputters pretty bad and backfires alot. no power it seems, i didnt push it really hard to find out tho. just turned around after like a block and came back home. i think my alternator is almost pooched because i boosted it this year with a completely dead battery that wont hold a charge and drove it for awhile like a week ago it seemed to run really good besides not able to keep the volts up, the altanator was already getting weak. Yesterday i just put a battery in from my beater an 88 K car to get it running to drive... and thats when the gauges wouldnt come on and this problem started. Its in an R32 GTR

Any help would be great!

thanks

[blk94r33]

Dangerous choice of username...

Is the alternator light on before 1500rpm?

Have you checked the voltage with a multimeter?

[ChuckNorris]

yeah maybe! haha. there is no lights on at all. untill i turn it over theres nothing but the noise form the fuel pump... im gunna pick one up tomorrow!

[fastjetjockey]

Yeah mate, chuck a meter across your alternator and see what voltage it's putting out. Should be between 13 and 15 volts for normal charge. If it's below that it could be your whole alternator (brushes etc) or just your voltage stabilizer (which is like a $70 part).