BlueBallz

I was out for a drive and noticed my voltage gauge kept fluctuating at stop lights/signs. If I was driving and maintaining a speed there was a little movement but not as bad as if I was stopped at a light/sign idling. If I have the car in park it seems to idle high enough not to be effected as much. But as soon as I shift into gear it does it. I can see the gauge move a lot and all the lights start to flicker. It would drop below 13 volts and pick up over 14 volts again. I tested the battery with everything off and it read 12.8 volts, so I assumed it was the alternator. I replaced the alternator with a new one, not remand. The voltage fluctuating stopped fluctuating as bad, but still does it. After replacing the alternator, at the battery I'm reading 14.2 volts while running in park at idle and 12.8 volts with all power off. Even currently at idle in park after a minute or so you can hear the system struggle and see the lights dim/flicker and then go back to normal for another couple minutes till it does it again.

I've started looking at grounds, but so far they all seem fine.
I saw another forum post that lists a bunch of the engine grounds. Does anyone have anymore specific details on #4 I can't seem to locate that one under my air box assembly.
https://ls1tech.com/forums/wiring-st...s1-f-body.html
UPDATED:
#1: Back of passenger side cylinder head.
#2: Passenger side of block.
#3: 3 ground wires on the back of the drivers side head.
#4: under the bracket for the air box assembly. (can cause all kinds of light problems)
#5: cluster of ground wires on the lower ds pillar, close to the door pushbutton for the interior light.
#6: Grounding strap from just behind alternator. (PS fluid just loves to reek havoc in that area)

wssix99

iTrader: (5)

If you have an electrical problem that goes away when the engine picks up RPMs or takes off load (going in to Park or Neutral), then the first thing I would check are:
- The main serpentine belt
- The belt tensioner (There are marks on the tensioner that tell you if you have the proper tension on the belt and/or if it has elongaged.) https://ls1tech.com/forums/conversio...indicator.html (Post 8 shows good tension and a good belt.)