Commanding more voltage from the alternator

[BMWMD82]

Looks like this is the amperage curve of that alternator. Should be capable of ~200 amps at idle. Somehow I don't think the alternator is the issue.

Have you checked the terminal on the starter, Dave? I know those suckers love to melt, and maybe the turbos are making that more of an issue. Just a thought.



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[HRD]

It's rated 200 amps at 2250 rpm. Is the alt turning that much at idle? Check the pwr teminal on the alt with the engine running with a volt meter. I'll bet it's less than 13v. Alt is probably weak or turning too slow.

[BMWMD82]

It's rated 200 amps at 2250 rpm. Is the alt turning that much at idle? Check the pwr teminal on the alt with the engine running with a volt meter. I'll bet it's less than 13v. Alt is probably weak or turning too slow.

That's alternator RPM --- it says somewhere on that chart that it is usually 3-3.5 times higher than engine RPM. So at an 800 RPM idle, the alternator is probably spinning 2400 RPM.

[DSteck]

I honestly haven't messed with it at all. I probably should. Lol.

[5_Liter_Eater]

Interesting thread. I too have have low voltage at idle, particularly when hot, for some time now. i'ev just been living with it. I used to attribute it to a poor connection at the starter but when I had the motor out I moved the battery to the back and am no longer running the alternator through the starter lug. It goes battery to fuse block and fuse block to starter and fuse block to alternator. Voltage comes right up to ~14 at anything above idle so I did consider an overdrive pulley for it.

[gn2beatu]

Can you explain that a little more?

Its in the System Tab, under General.

You can change the minimum system voltage, how fast it responds to voltage drop, and how fast you want to increase it. EX: on 2007 TBSS, if its low for greater than 5 seconds it adds .2volts in increments til requested voltage is met.