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Hey,

I have some issues with my rb25det in r32. We tried to tune it but to no avail because the voltage keeps dropping. I tried two new alternators and niether one changed anything. I have check continuity from -ve and +ve from battery to alternator and i have checked voltage at alternator and battery and its the same both sides, and as the car runs the voltage keeps dropping.

I am really stuck!!! If someone can offer some ideas I would be very appreciative.

Thanks, Leon

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What sort of voltage are you talking?

I have always seen a slight voltage drop with mine; its nothing the volt vs ign, volt vs inj correction can't take care of.

As its a different motor my bet is the chassis/motor being poorly earthed.

Edited by TheRogue

its definately got good earth. There is 2 from chassis to battery and 2 from chassis to block, all on clean metal.

Not sure what alternator it is, its a 90amp mistu one. Can anyone tell me whether or not r32/r33 have internal or external volt regulators?

okay so they have internal regulators...

Now just wondering, ive been told the battery light should turn on in the dash when i key on for the alternator to be working properly... the light only comes on after driving and battery goes flat///

any ideas anyone?

  • 3 years later...

Hey,

I have some issues with my rb25det in r32. We tried to tune it but to no avail because the voltage keeps dropping. I tried two new alternators and niether one changed anything. I have check continuity from -ve and +ve from battery to alternator and i have checked voltage at alternator and battery and its the same both sides, and as the car runs the voltage keeps dropping.

I am really stuck!!! If someone can offer some ideas I would be very appreciative.

Thanks, Leon

I currently have the exact same problem. But mine is still a rb20 in r32 with voltage dropping under engine load.

Anybody got ideas?

Have you tried a new battery? This cold weather can make them fail...

I would guess the power through the dash light to the alternator may not be wired up correctly or open circuit? I seem to remember it need to be connected to charge correctly? I would be taking it to an auto elec.

The charge light MUST come on on the dash when you turn ignition on. It is the small current flowing through that circuit (and the alternator) that excites the alternator and lets it actually charge. If the light does not come on, then you either have a wiring problem, or the globe is blown (assuming no alternator fault).

It is that simple.

Edited by GTSBoy

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