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Hey,

When i have my headlights, foglights & radio on (aftermarket headunit with 1 working speaker in car) the voltage in my r32 gtst drops to 12.3v. It then fluctuates between 12.3 and 12.5v

The battery has been recently replaced with a 700cca battery as my old one went flat really quickly.

Is this a normal voltage for an idling r32 with a new battery?

Sometimes when idling at the lights, a slight vibration can be felt which only lasts for a second or two and then disappears. When this occurs the voltage seems to drop from 12.4 to 12.2~ and then back up once the vibration stops.

Would a dieing alternator cause this? Ive heard that the r32 is very sensitive to voltage changes which may cause the slight vibration during voltage drops?

Also, car struggles to jump to life on cold start-ups. When new battery was first placed in, the car would crank over real quick in the mornings. However now, (couple months after new battery) it seems to take longer than previous to crank, also a blip of the gas pedal has to be done to keep it running.

Thanks

Patrick

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Took it to auto electrician. Checked the voltage. My alternator isnt charging the battery on idle, hence why it sits on 12.3v~

Also explains my bad cold starts as the battery voltage is low and the low voltage affects the engine causing the vibration.

So guess its time for a new alternator ^^,

Took it to auto electrician. Checked the voltage. My alternator isnt charging the battery on idle, hence why it sits on 12.3v~

Also explains my bad cold starts as the battery voltage is low and the low voltage affects the engine causing the vibration.

So guess its time for a new alternator ^^,

I'm interested as to what u get for yr alt. Mine was rebuilt for $250 odd by a local auto electrician. I had it die on me 4 times before I popped a gasket and had a good old fashioned whinge.

First time they blamed the bearing. Second time they blamed the contacts. Third time they blamed the wiring. Fourth time they blamed the diodes. And then they tried to tell me that the alternator was dying because I "drove the car at very high revs".

cops arse.

Anyhow, I'm not quite convinced that this alt is the goods. Theres an amp rating for alts which affects the rate of charge. I dont know the values of stock or replacement units, but keep an eye out. Would be interested to know price and part numbers incase a replacement is required...

Thanks

-D

The alternator in the r32 is the same as the alternator in the ADM R31 skyline.

Bosch make brand new alternator for the r31 which has been proven to fit/work in r32's.

Part Number:

BXN1231

They retail for around $300.

Im sure there are other companies which produce alternators, just enquire for a r31 alternator and it should work*

*note i cannot guarantee every r31 alternator will work, its just something ive heard.

I'll be purchasing the bosch BXN1231 in a couple of weeks and will update with the progress.

Does anyone know that if you drive in flooded roads with lots of water going up in your car that this could somehow affect your alternator? My car wont even start as its only got 11.3 volts..... It doesnt do the ticking noise like when your battery goes flat, its more a failed start....It wont tick over :happy:, plus my alarm is screwed

  • 2 weeks later...

damn, I've been searching about alternators for a while, nothing on SAU.

When my Rb20DET is warmed up the voltage drops to like 12.1 volts on idle and on startup is gets around 13volts....

my alternator is dead too by the looks of it.....

does anyone know 100% if the plugs on the R33 alternator plug straight up? I know it bolts up, but from searching no one has confirmed it actually plugs up.

I just stumbled across this page, its from a bogan site, but its kinda handy...

http://www.calaisturbo.com.au/showthread.php?t=11447

120AMP alternator from a VS Commodore (Cop Special), apparrently all you have to do is switch the pulley over...

guys on the forum are saying VS commodore alternators fit onto RB30s, i.e. will fit on RB20 Rb25s someone confirm? if so I'm getting myself a 120AMP alternator!!

keep us updated with your progress johnnilicte.

I went to another auto electrician and he said my alternator was fine and that the voltage loss could be due to something draining the power..

Ill probably change alternator regardless as its well over 14yrs old.

Let us know which alternator you go for!

I had a similiar issue some time ago shortly after i dropped the new motor in.

replacing the earths with new and ensuring no paint on the mating surface fixed my issue.

I now see ~14v and 13.8 with demister, lights, heater etc all on.

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