About a week ago, I noticed the dashlights in my '87 Chevy Suburban V20 were pulsing at idle. I checked the output on the alternator, and it's showing almost exactly 15v. It drops down slightly to about 14.7 or 14.8 when engine speed increases. The pulsing only happens at idle.
Is my regulator dead in the alternator? Can this damage my battery? I bought an Optima Yellow Top for this thing and really don't want to destroy it.