Jump to content
SAU Community

Recommended Posts

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

Link to comment
https://www.sau.com.au/forums/topic/266144-rb25-voltage-problems/
Share on other sites

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

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Nah - but you won't find anything on dismantling the seats in any such thing anyway.
    • Could be. Could also be that they sit around broken more. To be fair, you almost never see one driving around. I see more R chassis GTRs than the Renault ones.
    • Yeah. Nah. This is why I said My bold for my double emphasis. We're not talking about cars tuned to the edge of det here. We're talking about normal cars. Flame propagation speed and the amount of energy required to ignite the fuel are not significant factors when running at 1500-4000 rpm, and medium to light loads, like nearly every car on the road (except twin cab utes which are driven at 6k and 100% load all the time). There is no shortage of ignition energy available in any petrol engine. If there was, we'd all be in deep shit. The calorific value, on a volume basis, is significantly different, between 98 and 91, and that turns up immediately in consumption numbers. You can see the signal easily if you control for the other variables well enough, and/or collect enough stats. As to not seeing any benefit - we had a couple of EF and EL Falcons in the company fleet back in the late 90s and early 2000s. The EEC IV ECU in those things was particularly good at adding in timing as soon as knock headroom improved, which typically came from putting in some 95 or 98. The responsiveness and power improved noticeably, and the fuel consumption dropped considerably, just from going to 95. Less delta from there to 98 - almost not noticeable, compared to the big differences seen between 91 and 95. Way back in the day, when supermarkets first started selling fuel from their own stations, I did thousands of km in FNQ in a small Toyota. I can't remember if it was a Starlet or an early Yaris. Anyway - the supermarket servos were bringing in cheap fuel from Indonesia, and the other servos were still using locally refined gear. The fuel consumption was typically at least 5%, often as much as 8% worse on the Indo shit, presumably because they had a lot more oxygenated component in the brew, and were probably barely meeting the octane spec. Around the same time or maybe a bit later (like 25 years ago), I could tell the difference between Shell 98 and BP 98, and typically preferred to only use Shell then because the Skyline ran so much better on it. Years later I found the realtionship between them had swapped, as a consequence of yet more refinery closures. So I've only used BP 98 since. Although, I must say that I could not fault the odd tank of United 98 that I've run. It's probably the same stuff. It is also very important to remember that these findings are often dependent on region. With most of the refineries in Oz now dead, there's less variability in local stuff, and he majority of our fuels are not even refined here any more anyway. It probably depends more on which SE Asian refinery is currently cheapest to operate.
    • You don't have an R34 service manual for the body do you? Have found plenty for the engine and drivetrain but nothing else
    • If they can dyno them, get them dyno'd, make sure they're not leaking, and if they look okay on the dyno and are performing relatively well, put them in the car.   If they're leaking oil etc, and you feel so inclined, open them up yourself and see what you can do to fix it. The main thing you're trying to do is replace the parts that perish, like seals. You're not attempting to change the valving. You might even be able to find somewhere that has the Tein parts/rebuild kit if you dig hard.
×
×
  • Create New...