Charging at 16+ volts, new alt & bat, help? 92 ciera

[randini667]

Here's the background information for my problem: Most commonly, when my car is cold, it starts up fine, and I have no concerns. Commonly after driving the vehicle for about 15 mins or 10 miles or so, my charge light will come on and off sparadically. I decided to poke my volt meter around getting various readings. Here is my problem: When the charing system is acting up, it runs at 16, 17, sometimes 18 volts. It is not related to RPM speed, once the problems pops up, it will do it at idle too. Quite often I quickly notice when it kicks in because my interior lights, headlights, instrument panel, will all get extremely bright. It almost acts like when I start the car, the alternator chargers normal rates 13-14 volts, but when the battery is fully charged, it goes beserk!

Things I have checked and tried

• New battery, +tested good
• Replaced alternator twice (just to make sure, plus under warranty)
• Replaced alternator with 2 used ones just to check
• Grounds are solid, checked multiple locations

I have no idea what to do next. For the moment, I just make sure all my trips are short and sweet because I boiled one battery to death on a 400 mile trip I took home for Christmas. Can anyone make my sad story a happy one?

-Randy
1992 Oldsmobile Ciera 3.3L

[xeroinfinity]

Hi Randy,

Do you have a wire diagram like this one.

It shows the fuse links from the alternator and the one by the battery.

Also check that the wires on the starter are clean and tight.
Or that they are connected right if they have been off recently.

Let me know what you find out.

[randini667]

Ok, here is my update. Couple of goodies here:

Fix 1: I probed all the wiring in relation with the charging system. I found one red wire that should be hot, but was not (rediculous rhyme ). I traced the wire to the alternator plug. Definately a problem there. On the other end it was linked into another wire, then secured to the hot post on the starter. So I cut out the link and took a look it inside and cracked it open. Actaully you can't crack these open, but my soldering iron and some pliers worked. This picture will demonstrate what I found:



Lots of corrosion! Soo much that there was no contact. So I spliced the wires together and put some shrink tubing and electrical tape around it. I am now getting a hot response to the wire.

Fix 2: The junction post on the starter for all the hot wires was loose, but I think that was from me taking off all the wires to fix the bad one, then agian, it may have just been loose? Not sure on that one, but anway, it's tight on the starter now.


It's hard to say what will happen with the car now. It will take some time on the road and in various situations before I can report any changes. Thanks for the help, much appreciated!

-Randy

[xeroinfinity]

!

Sounds like you found the problems.

Keep me posted on how it is working

[randini667]

Just to follow up, all things have been going smooth! There are no signs of any problems with my charging system. Just in time for the cold weather to roll in.

-Randy