Voltage drop problem BMW 325i

[Wicks]

I asked him about regulator and he said it's got nothing to do with it.

Hopefully belt will fix the issue.

Feel the belt after playing full tilt for a while. If it is superhot then that is an indication of belt slip.

With the voltage drop I'm having right now, I'm afraid of blowing amp.

Have a battery load tester (REALLY big resistor)?

Auto parts store may have one, or two.

Could use that and draw power from the alt for a while and see...

Might not be enough load though to cause belt slip.

[LoudBimmer]

The new belt should be shipped out tomorrow.

Worst case scenario is I will ship it back to Mike so he could double check it.

[LoudBimmer]

Well, the 57.5 belt was way too short.

What I noticed was that the voltage stays at 14.0v at 2-3-4-5k rpm, but as soon as I let the gas pedal go, it still stays at 14.0 5-4-3k rpm and as soon as it passes 2k rpm voltage would drop to low 12's and climb back to 14.0.

So it does look like there might be something wrong with an alternator after all.

[LoudBimmer]

I just tried one more thing. I turned the heat all the way up and also head lights on. The voltage (at idle) went from 13.8 to 12.0-12.2.

[Guest]

how old is the belt tensioner?

[LoudBimmer]

I think it's original.

[Guest]

I think it's original.

how many miles?

[fox_racin4]

Whats your idle speed?

[LoudBimmer]

I think it's original.

how many miles?

~160k lol

I'm ordering new one right now.

Whats your idle speed?

~700rpm

[Guest]

lol god damn. that thing is worn out to shit.