CHARGE MYSTERY help!

[BobbyBeamer]

91 525i YES THIS WILL ALL SOUND FAMILIAR But.......

Having that very common problem with the ALT/BATT/DIM LIGHTS/TRAnS PROGRAM etc...... I have read a ton of posts about this but
HAS ANYONE EVER HEARD OF THIS????????

across the battery posts....around 12 v (normal) w/car off
start the car.....A MISERABLE 11.5v (should be around 13-14 indefinitely)

HERES where it gets good....at 2000rpm and full load (everything on)
13-14 good voltage,but NOT every time. Turn off start again 11.5 v and that hurts cause it draining a new battery. WHEN IT DOES TEST GOOD IT ACTUALLY DOES ITS JOB TO CHARGE.
Crazy stuff........battery is new, alt(reman 6 mos.) ago bench tested 14.2 perfect.

Draw test .4 amp .........Bentley manual says .5 and above is unnaceptable
What was it that was heat or time related?? diodes in the alt open up er something? If that was the case, an alt bench test for 45-90 mins should determine that right?


thanks in advance