Weird voltage spike issue (intermittent)

[LC1979]

I have a 1992 3fe and have a weird voltage spike issue. Today, I was driving and had the voltage spike up with RPMs to a high of 18v. It only lasted a minute or so of driving. I had this happen about 3 months ago also. My question is, does this sound like a voltage regulator problem? AutoZone alternator (I know) about 5-6 years old. Got it tested at O’Reilly about a month ago in between the spikes. They said it was good.

I’m also currently dealing with a intermittent idle issue.

 

[gnob]

Yes, sounds like a reg. Had a similar issue once with a bosch. VR started going bonkers. I would notice my dash lights surge.

 

[LC1979]

Yes, sounds like a reg. Had a similar issue once with a bosch. VR started going bonkers. I would notice my dash lights surge.

Yeah. Dash lights got awfully bright both times. I just found it weird to go 3 months in between spikes.

 

[LC1979]

Thanks gnob. Anyone else have a similar issue in the past?