voltage drain at idle and stumble help

notch351

Member
Jul 30, 2010
110
2
19
I have a 93 notch with an efi 351w. I have recently started to get some sort of voltage drain at idle and when it does this the engine kind of has a little stumble. pretty consistant issue rpm doesn't seem to change to much think the stumble is more from possible lack of spark power when volts drop. any ideas. just for kicks I have a one wire alternator not to familiar with these so i THOUGHT I would mention that could the regulator in the alternator cause this possibly
 
  • Sponsors (?)


Does this happen after you've achieved the self-excite threshold for the alternator?

Why do you think you have a voltage drain? Do the volts drop real low at idle? Do you know an exact voltage reading at idle (when it acts up)?

If the battery is charged, low-alt output should not really affect things.
 
I had the exact same problem with my 92. I replaced the alternator with a PA Performance 130 amp kit and it cured the issue. It's a completely different car where it doesn't buck at low RPM or have a massive voltage drop at idle.