I have 77 240d that I am getting small voltage drop or spikes (depending on which one it is). Here's a better explanation. I am seeing the lights; headlights, interior, and gauges showing small pulsations as I drive down the highway at night. Not severly like it looking like I am flashing my brights, just enough to notice. Is this the sign of a voltage regulator going? Or is this normal for diesels as this is my first? The alternator was replace within the last year and battery within the last 6 months.